In Kyllo v. United States, 533 U.S. 27 (2001), the Supreme Court held that it violated the Fourth Amendment to direct an infrared thermal imaging device at a home without a warrant to determine the home’s temperature. This post asks whether that result is still good law. I realize that probably sounds a bit nutty at first, as Kyllo is only a few years old. But Kyllo deliberately adopted a test designed to let the result change with social practice . This post asks whether changing social practices already allow the police to use thermal imaging devices without a warrant.
I’ll look at the problem in three steps. First, I’ll explain the relevant Fourth Amendment test from Kyllo. Second, I’ll explain how technology and social practice have changed in the eight-and-a-half years since the Kyllo decision. And third, I’ll put the pieces together and ask whether Kyllo‘s result remains good law. My bottom line: I’m not really sure, but there is a decent case to be made that the police can now use thermal imaging devices without a warrant consistently with Kyllo.
I. Kyllo and General Public Use
In Kyllo, the police used an infrared thermal imaging device called an “Agema Thermovision 210″ to scan a suspect’s home from the city street. The scan tool a few minutes, and it revealed that the roof over Kyllo’s garage was unusually hot — a sign, the government though, that the suspect was growing marijuana under heat lamps in the garage attic. The Supreme Court announced the following rule: “when . . . the Government uses a device that is not in general public use, to explore details of the home that would previously have been unknowable without physical intrusion, the surveillance is a “search” and is presumptively unreasonable without a warrant.” Because infrared temperature sensing was not in “general public use,” the thermal imaging was a “search” that required a warrant.
There are several ways to justify the “general public use” limitation on the result in Kyllo. Perhaps the idea was that if a technology is widely used by the public, it is not longer reasonable expect that it won’t be used. This reflects what I have called the probabilistic model of Fourth Amendment protection, and is hinted at in footnote 6 of Kyllo. Alternatively, perhaps the Court was trying to square the result in Kyllo with cases going back to the 1920s that that had allowed the police to use flashlights. See United States v. Lee, 274 U.S. 559, 563 (1927); United States v. Dunn, 480 U.S. 294 (1987) . After all, flashlights are devices used to explore details previously unknowable without a physical intrusion, and yet they have always been allowed.
Whatever the reason for the limitation, it indicates that when remote infrared temperature detection devices enter general public use, the police can use them, too. Justice Scalia had no problem saying that such devices were not in general public use in 2001. In response to the dissent’s claim a hearing was required to determine how many of the devices were used, Justice Scalia responded that the majority was “quite confiden[t]” that the devices were not in general public use.
That seemed right in 2001. But what about now?
II. Common Uses of Thermal Imaging Devices a Decade After Kyllo
Fast forward a few years, and remote infrared temperature-sensing has become quite common in a wide range of applications. The most widely-used devices are “single point” thermal imagers that are widely marketed to the public as infrared thermometers. These devices are akin to temperature guns: They tell you the temperature of whatever surface you’re pointing it at, usually aided by a laser sight to tell you exactly were you’re aiming. Here’s a Black & Decker model available for $50 at Amazon (with free super saver shipping, and note the 43 glowing user reviews). I myself bought a Raytek ST20 for about $120 two or three years ago. You can see how it works in this short video:
These thermometers have entered widespread use in recent years for a wide range of applications. For example, here’s an advertisement of an infrared-sensing device marketed to moms to take their babies’ temperatures:
More often, the devices are marketed to individuals for automotive or home insulation use. The ability to pinpoint surface temperatures helps you know where you need to insulate your home better for the winter; it also lets you find short circuits or know if an engine or electrical device is dangerously overheating. These devices seem to have entered the mainstream, as I see advertisements for them in catalogs. Here’s an advertisement that gives you an idea of typical uses:
Although the the single-point devices marketed to home users are in the $50-$150 range, the full-camera models now start around $2,000. Here’s the FLIR/Extech i5 handheld thermal imager available from Amazon for $1,995. These cameras don’t just give a single point temperature reading. Instead, they give you a full picture in real-time. In effect, they take a readings from lots of individual points and assemble the readings graphically to give you a full image of the temperature. Here’s an advertisement for one of the full-camera models that is aimed at property managers and HVAC companies:
III. Is the Result in Kyllo Still Good Law?
Ok, so that’s the current state of the technology. Now let’s go back to the Fourth Amendment.
The various devices I have described can be used to do what the government did in Kyllo, namely find a “hot” portion of wall or roof on a house. I’ve tried this on my own house with my Raytek ST20, the one I bought for $120 a few years ago. I stood in front of my house in the winter, when I knew the furnace was up and running, and I pointed the device at the exterior walls of my home. By scanning up and down and side to side from outside the house, I could see the rough outlines of where inside the house the radiators were located. It turns out that the radiators create hot spots on the wall next to them that make those portions of the exterior wall around 5-10 degrees warmer than the rest.
So here’s the question. Can the police use these devices now? Are either the single-point or full-camera infrared imaging devices in “general public use”? Imagine a police officer goes on Amazon and buys the $50 Black & Decker model and directs it at a home to look for hot walls that might reveal marijuana lamps. That was a “search” in 2001. But is it a “search” in 2010?
Also, does it depend how you define the “device”? When the Supreme Court enacts special rules that regulate certain technological devices, there is always the level of generality problem in interpreting the rule. You need to figure out how broadly or narrowly to construe the “device” covered by the rule. For example, perhaps you might say that all of the single-point infrared sensors are one “device” and the full-image sensors are another, and perhaps the former is in general public use while the latter is not? (Perhaps this is arbitrary, but then maybe not: After all, the single-point devices don’t automatically generate an “image,” and therefore perhaps are not “thermal imaging devices” even if they yield the same information.) Or perhaps they should all be grouped together?
To be clear, I am not posting this to be critical of Kyllo (although I have been critical of it elsewhere for other reasons). Rather, I am just trying to figure out how the case applies a decade or so later. Kyllo deliberately adopted a rule that allows the outcome to change along with society: I’m wondering if the intervening changes in society, as seen in Part II above, mean that the devices that the case prohibited without a warrant can now be used. I can’t be sure of the answer because the courts have never elaborated on the test for “general public use.” (Just how “general” is general enough?) But taking the case seriously, it seems to me that there’s at least a plausible case that the police can now use thermal imaging devices — or at least the simple single-point infrared devices — without a warrant.
notaclue says:
Seems to this non-lawyer that easy, cheap public availability ought to support a “general public use” claim. Anything you can buy on Amazon for under $100 differs hugely from special surveillance equipment.
[OK Chimes in: So where would you draw the constitutional line as to what the police can use?]
January 4, 2010, 12:54 pmhf says:
The use of the device doesn’t seem as problematic as the claim that having a warm spot in your house constitutes probable cause, or even a significant part of establishing probable cause.
[OK Chimes in: You may be right, but that's not within the scope of the Kyllo decision]
January 4, 2010, 12:57 pmAF says:
Point taken that “general public use” is a bad test, but disregarding Kyllo strikes me as far from “plausible,” at least for a lower court or a police department. Infrared devices may be easier to buy today than they were in 2001 — and I assume they were already available then — but they have hardly reached the point where there is no reasonable expectation of privacy for generating heat inside your home.
[OK Chimes in: Based on what, AF? The Kyllo court phrased the test as "general public use," not as use so common that you have no reasonable expectation of privacy. Indeed, Justice Scalia was rather contemptuous of the "reasonable expectation of privacy "test in Kyllo. In other words, what do you think is the correct result based on the test the supreme court adopted?]
January 4, 2010, 1:01 pmdave h says:
I’m with hf. If your radiators created hot spots, how does this give the police probable cause? At least at the current state of technology the detection of heat generated in your home is less of an intrusion than the resulting search.
[OK Chimes in: It doesn't, and no one is claiming it does. Exactly how much cause it provides is outside the scope of Kyllo, and I was trying to stick to Kyllo. Also, I am deleting the two comments below that also want to talk about to what extent does a heat profile really generate probable cause. That's not what the post is about, so I was hoping commenters could stick to the issues raised in the post.]
January 4, 2010, 1:06 pmDJR says:
Given the prevailance of nanny cams, invited guests and overnight guests no longer have a reasonable expectation of privacy in another’s home.
January 4, 2010, 1:17 pmTim says:
Of course it’s a search in 2010. The question presented borderlines on absurd. The entire purpose of the 4th Amendment’s warrant requirement would be invalid if some electronic tool could be used to gather evidence that is not in plain view.
Warrants are the rule, not the exception. What kind of libertarian law blog would suggest that such an important right as this one be invalidated because something is general public use?
Perhaps your criticism is taken, that the test for what would be a search should be better. But of course it’s a search, that’s the whole point.
[OK Chimes in: Tim, given that you're planning to go to law school next year, one piece of advice, from a law professor to a future law student, is not to call your professors' questions within their area of expertise "absurd," suggest they don't know "the entire purpose" of the Constitution, or express dismay that your professors are not letting their personal politics govern what they say the Constitution means. Just a thought.]
January 4, 2010, 1:21 pmOren says:
Anything that can be seen from the street is fair name for your nosy neighbors and the police alike.
An interesting conclusion Orin.
Assuming that’s true, does an officer violate the 4A by using a SPID over on an array of points on the outside of the house and recording the results on a (dead-tree) spreadsheet? If so, then it’s a quick step to scanning that into a computer to make a false color image (or even doing so manually with considerable patience). I’m not aware of any cases in which some transformative use of data (for instance, collating the SPID readings into an image) has been found to turn a legal search (or a non-search) into an illegal one.
To me, then, the issue is that the full-imager is legally equivalent to the SPID — it only automates a process that cannot change the legal status of the search — and that they must either both be illegal or both not.
January 4, 2010, 1:22 pmOren says:
One that acknowledges the plain fact that the law as it exists is insanely far from embodying libertarian ideals.
There are plenty of blogs that will give you page after page of wishful thinking about how the law agrees with their ideological preferences. One reason I read the VC is that the conspirators are fairly scrupulous about delineating the difference between analyzing the law as it current exists and expounding on how they think the law ought to be.
January 4, 2010, 1:26 pmAF says:
Based on what, AF? The Kyllo court phrased the test as “general public use,” not as use so common that you have no reasonable expectation of privacy.
Only an idiot would debate Orin on 4A case law, but footnote 6 strikes me as relating the “general public use” test to the “reasonable expectation of privacy,” if only as a matter of following precedent:
In other words, what do you think is the correct result based on the test the supreme court adopted?
I would say the correct result is to follow Kyllo until (1) the Supreme Court overrules it, or (2) the use of infrared technology to peer inside houses becomes comparably prevalent to the use of airplanes or flashlights.
January 4, 2010, 1:34 pmxon says:
I think Kyllo stands for the proposition that the government’s leveraging of the extreme disparity in resources available to the government versus the private citizen creates search methods that are, per se, unreasonable. The flashlight example is a good, if extremely rudimentary, example.
I don’t think Kyllo stood for the idea that police couldn’t use whatever technology they can to detect crime. Rather, it stood for the prophylactic purpose of deterring a surveillance ‘arms race’ where the governments had a perverse incentive to rush down the road to satellite surveillance of corner drug markets and the suburbs, in clear (perhaps even to Scalia) detriment to what we consider basic liberty. The unintended consequences of criminals innovating new technologies and techniques to defeat ever more and more expensive government surveillance is the other half of the Lose/Lose situation we might be in but for Kyllo. The question one might ask is: “How much did the equipment we were using to eavesdrop on Osama Bin Ladin’s satellite phone cost, since he stopped using it as a consequence of a newspaper article?” Several very high dollar intelligence systems were obsolete in advance of their initial deployment due to either compromise or the development of countermeasures. How would a county’s budget deal with that kind of situation?
January 4, 2010, 1:34 pmPaul McKaskle says:
Kyllo has always struck me as a tempest in a teapot. I don’t know what actual practice has been for marijuana cops, but I can quite imagine them using temperature sensors to pinpoint likely indoor marijuana growing locations and then increasing lawful surveillance and related investigation to develop sufficient probable cause for a warrant. It wouldn’t always work, but it is certainly a lot easier to develop at least probable cause for a physical search if you know in advance where the “crime” is being committed.
January 4, 2010, 1:41 pmI suppose the subsequent investigation might be deemed a fruit of a poisonous tree but I also suspect that it would be very hard to establish that an initial unlawful search using temperature sensors had occurred if the cops denied using them. As I said above, I have no idea of what is actually happening in this area and I realize that a truly ethical police department would never use this subterfuge.
David Schwartz says:
I think you’ve flipped Kyllo on its head. The whole point of Kyllo was to ensure that results did *not* change with technology:
Reading the “not in general public use” in its context, Kyllo specifies a fixed standard frozen in time, not one that erodes privacies as the technologicals blow.
[OK Chimes in: David, I think you are confusing the standard with the outcome of the standard. Kyllo adopted a fixed standard that allows the outcome to change as general public use changes. To be sure, it leaves privacy fixed so long as the new devices are *only used by the government,* not the general public. But the test allows changing practices by the general public to change the outcome of the standard.]
January 4, 2010, 1:47 pmOrin Kerr says:
Thanks very much for the clarification, AF.
As for the second point, lets assume that the Court means to take the reasoning of Ciraolo seriously — an open question in my view, but let’s put that aside — and that the key question is the frequency that a person would reasonably expect to be surveilled from overhead by commercial or private aviation. I guess my question is how you measure that, and how you compare that to the frequency that a person would reasonably expect to be monitored by an infrared device. The question is, have the widespread uses of these technologies made the devices in general public use, and how would you know?
One of the reasons I’m interested in this aspect of Kyllo is that before Kyllo, the Court never took this type of probabilistic reasoning very seriously. The Justices in Ciraolo and Riley used probabilistic language, but it seemed, at least to me, like they just added it for show and that it wasn’t very central to the opinion. That meant you never really had a case that raised exactly how to apply a probabilistic test. Kyllo then took that language seriously for the first time, and the changing technology suggests that we may soon see challenges asking the courts to say for the first time what that sort of inquiry is supposed to look like.
January 4, 2010, 1:47 pmdave h says:
The reason I brought up whether the thermal scan met probable cause was because the resulting search affects how people think about the initial thermal scan. I would feel my privacy were unreasonably violated in this particular case only by the later search, not the initial scan. I would change my mind if the initial scan because so advanced that details of my life could not be kept secret, though then presumably I would have some countermeasures available to me. I suppose this is why the court chose this standard – it keeps the police from being able to use advanced, expensive technology before it has become commonplace enough to warrant adequate countermeasures.
January 4, 2010, 1:56 pmDavid Schwartz says:
OK: Why do you think it immediately says: “This assures preservation of that degree of privacy against government that existed when the Fourth Amendment was adopted.” The whole point of the ruling in Kyllo was that the police *cannot* say “well, we don’t need a warrant to get information X because now we have technology Y”.
If you have an expectation of privacy and that expectation is reasonable, police technology cannot erode it. That’s what Kyllo says. You’re taking the “not in general public use” part completely out of context. (Which more or less means that public use of a technology can make previously reasonable expectations of privacy become unreasonable.)
January 4, 2010, 1:57 pmAF says:
I guess my question is how you measure that, and how you compare that to the frequency that a person would reasonably expect to be monitored by an infrared device. The question is, have the widespread uses of these technologies made the devices in general public use, and how would you know?
If I were a law professor or a Supreme Court justice (or clerk) — or a lawyer for a police department looking to challenge Kyllo and willing to take the accompanying risks — I would think deeply about that question, and probably conclude that the answer was sufficiently ill-defined that I was entitled to give it content through a novel analysis of my own devising.
On the other hand, as a workaday lawyer advising a typically risk-averse client, or even as a clerk for a lower court judge, I would apply a more pedestrian thought process. I would start with the strong presumption that the result in Kyllo has to be followed unless there is a very compelling reason to believe that its reasoning is obsolete. I would then look at the prevalence of infrared temperature sensors as compared to the prevalence of the practices identified in the applicable precedents, eg air travel and (per Orin) flashlights. If the use of infrared sensors approached the prevalence of air travel or flashlights, I would say there was a plausible case to be made that the result in Kyllo has been superseded by events. If not, not.
January 4, 2010, 2:12 pmFantasiaWHT says:
My big beef with Kyllo differs from most… the devices do NOT measure the heat “inside” the home. They measure the heat radiating from the OUTSIDE of the home. I see a huge parallel between drug sniffing dogs – they technically aren’t sniffing things inside the packages, their sniffing the tiny particulate that makes it outside the packages.
Would the result be different if, instead of a sensing device, some animal that sees well in infra-red was used instead?
January 4, 2010, 2:16 pmOrin Kerr says:
David Schwartz,
I think your interpretation of Kyllo is just flatly wrong. You’re overlooking the critical difference between when the government starts to use a technology and when the public does so.
Recall how Scalia begins part III, the analysis section:
You seem to interpret Kyllo as saying that technology has no power to shrink the realm of guaranteed privacy. But I think it’s pretty clear, from the quoted passage and the others I rely on in the post, that Scalia has something quite different and much narrower in mind. Scalia thinks it would be “foolish” to think that changing technology does not erode privacy: I think it is odd to interpret his opinion as adopting a position it calls “foolish.”
January 4, 2010, 2:24 pmOut of Iowa says:
If Madison would have thought it was a search in 1791 then it is still a search today.
I recognize this is not an exact analogy but I couldn’t come up with a better one fast enough:
Would Madison have said anything bordering “While I think that the British entering my home unauthorized and without knocking is a search today, the more often my fellow colonists adopt the practice of entering homes uninvited and without knocking in the future the less I think I’ll have an expectation of privacy and therefore I will not consider the practice a search some day.”?
January 4, 2010, 2:27 pmOrin Kerr says:
Out of Iowa,
At the time of the framing, I don’t think it occurred to anyone that anything other than an actual physical intrusion would be a search.
As for your question, it’s one of the problems with the probabilistic approach to Fourth Amendment protection — that is, the idea that what is a search depends on what is common versus what is rare. The court uses it sometimes and sometimes rejects it as obviously wrong: There are precedents on both sides, as I detail in my Four Models paper linked to in the post. That’s why Scalia’s relying on Ciraolo was a bit odd: Sure, the court took that approach in Ciraolo, but there are tons of cases in which the court has rejected the same approach. Why adopt it here?
January 4, 2010, 2:35 pmMonty says:
Due to the price point of the thermal imagers, I don’t think they are in “general public use” yet. Sure, at $2000 for a cheap model they may be getting adopted by specialized sectors of the economy, but they aren’t in many households. I would say you need to wait untill the products are being targeted at average home owners, or being included in consumer video cameras before they are really in general public use.
The point thermometers probably are now in general public use, but to achieve the same level of intrusion presented by the imager, the police would need to use the device in a very different way then most people do. I think you still need a warrant to use a device widely available to the public in a novel way that is vastly more intrusive then the normal use.
January 4, 2010, 2:36 pmJavert says:
Can the police use those devices without a warrant? Why not? They’re using all manner of such devices, without a warrant, at airports. If the Fourth Amendment be damned at airports, why not at homes? (Sarcasm off.)
January 4, 2010, 2:37 pmCrunchy Frog says:
Were Kyllo to be revisited today, the $50 SPID units would probably pass muster, while the $1500 thermal imaging unit would not. As much as I detest balancing tests, the one in Kyll makes sense.
Consider: under today’s Constitutional regime, the local gendarmerie (say the LAPD) could march drug sniffing police dogs up and down every street in the city and get results that would hold up in court. That is doesn’t do this is a matter of limited resources. Instead, it uses them in a manner that does the most good.
Similarly, a cop could take hours out of each day to do a detailed SPID map of all the buildings on his beat, but that would be prohibitively expensive in terms of his time, and in departmental manpower. So instead, there has to be some sort of standard by which any particular unit would be targeted. Call it, oh I dunno, “reasonable suspicion”.
Contrast that with the megabuck TI unit that lets you hit a whole house within seconds. There is nothing that would keep Officer Joe Fuzz from conducting a daily fishing expedition as he was going about his appointed rounds.
January 4, 2010, 2:38 pmToby says:
I am very depressed that Orin is right, and that the general public use will completely erode the 4th amendment in the way the commerce clause has completely eroded the 10th. With utilities adopting smart grid technologies across the board, the technology for complete awareness of all the activities in a home or business is becoming pervasive – and it is hard to deny “general public use” with the scale of current deployments…
A technical report published more than a decade ago described recognizing the level of activity on a waterbed from an electrical monitor outside the home. Sharing how often you use your exercise equipment would be easy to share with Health Management Authorities, if such existed, or with insurance companies in a market like today’s
An excellent general report can be found at:
http://www.ipc.on.ca/images/Resources/pbd-smartpriv-smartgrid.pdf
I wish that I thought Orin was wrong; under Kyllo, I think that police can use about anything. To me, the philosophical bases of the 4th amendment always had a privacy component, a concept that if we can’t tell you are doing it, then the law itself might be outside the bounds of propriety—sort of a formalization of “as long as you don’t do it in the streets and scare the women and horses”. Kyllo eroded that aspect.
January 4, 2010, 2:42 pmnotaclue says:
Orin, I referred only to the “general public use” issue, but if you want to hear my non-professional views on the main issue, all right.
As a citizen I would like to see the police limited to the most obvious of plain-sight surveillance without a warrant: no thermal imaging, no peeping in windows with or without electronics, no listening at keyholes or the electronic versions thereof, etc.
January 4, 2010, 2:43 pmAnderson says:
I don’t think it occurred to anyone that anything other than an actual physical intrusion would be a search
I don’t think it occurred to them that people could see through walls, either.
The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures
“Secure in their houses” is interesting. Most houses, I infer, are not secured against infrared snooping — I presume that such snooping could be insulated against, but that this would be expensive and most houses aren’t built like that.
Does that fact have any bearing on whether a thermal scan violates the security of one’s home? There are gadgets, aren’t there, that can pick up one’s telephone conversations — does that mean that one has no reasonable expectation of privacy in a phone call?
To the extent that Kyllo makes Fourth Amendment protections depend on what’s in the Sharper Image catalog this year, it seems like a bad decision.
January 4, 2010, 2:47 pmChris Travers says:
If you are sticking to Kyllo and asking whether it is still a search, I think the fundamental answer is that we don’t know. However, the general use test strikes me as quite problematic.
For example, we can certainly conclude that mm-wavelength scanners can be used to create something like a virtual strip search. If, at a later point, general use devices enter the market using mm wavelength scan technology (not sure what the application is at the moment), that shouldn’t make it any less of a strip search.
It further strikes me that the point of your post is to suggest that Kyllo is no longer good law because either the rule or the holding might have to go. If I had to choose, I would think that the court would keep with the holding and discard the rule, but I am not sure what would replace it.
My reasoning is that image-based thermal scanners might not have been in every household in 2001 but they WERE used for checking insulation from a much earlier time (I remember seeing some demos in the early 1990′s specifically for that purpose). One might argue that the court got the facts wrong in Kyllo (regarding general use), but I don’t think that is a very satisfactory way to overturn a ruling. I also don’t think that the Constitution allows 4th amendment analysis to take into account the price of the scanner involved, so the fact that it has become within the means of more people shouldn’t affect the analysis.
What this means is that I am left with a sense that the court got Kyllo deeply wrong and that a future court will have to correct that error. At the same time, I assume I, as a private citizen, have the right to go scan the houses of various police officers with this sort of thermal scan technology. So, I can see the argument that Kyllo poses no Constitutional problems to re-implementing this sort of thing.
Maybe the solution is at the legislative level, or maybe one could suggest that this is just short of a search, and that while the police could scan houses where they had other reason to think marijuana production was occurring, blanket scans of neighborhoods would be Constitutionally equivalent to roadblocks set up to catch drug smugglers (over the line).
January 4, 2010, 2:49 pmGuest12345 says:
I have no real idea about outside IR usage, but the idea that wide spread public activity lowers the barriers to government activity is a bit worrying. Consider:
1) Google, Yahoo, Microsoft, Apple, Alexa, etc. all do their absolute best to track user’s web browsing. At what point does this mean that the government will be allowed to begin tracking and logging user activity? The interesting aspect of this is that the majority of the networks within the US are privately owned and even when your data is traversing a third party network, fourth and fifth parties cannot readily watch your traffic.
Or ridiculously:
2) Various thugs engage in home invasion robberies. Will there come some point when the police can say, “Well, there are fifty home invasions a day in LA county. That is common enough for us stop considering a person’s home as ‘private.’”
It seems to me that the question should be whether basic privacy rights should be protected regardless of technology.
Another way that these kinds of questions could be answered would be to consider how the government would respond if new technologies were used by citizens to observe the Supreme Court Building, White House, the Pentagon, CIA/NSA/FBI headquarters or random federal prisons. I’m of the opinion that since government authority comes from the people, that individuals should be free from inspection to the same extent government offices are protected from such inspection.
January 4, 2010, 2:53 pmChris Travers says:
Re-reading Kyllo, I have a nitpick:
The syllabus states:
To be precise, it doesn’t say that sense-enhancing technology of this sort is Constitutionally allowed when in general use. It just says it is NOT allowed without a warrant when it is not in general use. This then suggests that going back to whether a search has occurred falls back on Katz analysis (i.e. is there a reasonable expectation of privacy, and is society willing to legitimize that expectation). I think Katz would still support ruling it as a search. Prof. Kerr, do you disagree?
January 4, 2010, 3:10 pmJeff J says:
To determine whether a device is in general public use, wouldn’t one have to decide — not only whether the device is widely available to the public — but also whether the public widely uses the device in the same way as police? For example, is there any evidence that people who own these devices use them to scan other people’s property with any frequency?
January 4, 2010, 3:10 pmJeff J says:
This makes me think about those cheesy commercials I’ve seen for over-the-ear listening devices that supposedly allow a user to hear quiet conversations across a crowded room or from a considerable distance away. Kyllo’s rationale suggests that the widespread marketing and availability of this product (if it actually works) might allow police to use it to listen to conversations, say, inside an apartment, that they would otherwise be unable to hear.
January 4, 2010, 3:17 pmRoscoe says:
This is a bit off topic, but back in the day (well before Kyllo) I used to fly an infrared equipped aircraft. We kept the system on all the time, so I guess that under Kyllo my backseat and I were violating hundreds of citizens’ “reasonable expectations of privacy” on every flight.
There are a lot more infrared equipped aircraft in service today. And I am willing to bet long odds that the pilots keep the systems on and train with them over civilian territory, just like we used to do. I don’t know that anyone cares (for the record, what you can glean about the inside of structures with an infrared unit is pretty trivial).
So, I wonder if Kyllo has anything to do with protecting privacy and constitutional values, or is it just a game for defense lawyers.
January 4, 2010, 3:22 pmJoeSixpack says:
I see a lot of commercials for a mail-order device that supposedly allows people to eavesdrop on conversations from over 50 yards away. The answer to this question may be obvious to those of you better versed in 4A law but is the government allowed to use listening devices to eavesdrop on conversations, given that these items are in general public use?
My hunch as to the Court’s thinking on this was “we don’t like the use of infrared, but we think flashlights are okay. Let’s come up with some kind of standard that allows flashlights but not infrared.” Of course, this worked at the time but it’s hard to imagine what will be in common use in the future (think, for example, of what people predicted the future would be like in the sixties). A case will be brought on this and the Court will take it and come up with a different standard that does not allow infrared sensing regardless of whether it is in general public use.
January 4, 2010, 3:22 pmJoeSixpack says:
Jeff J funny we thought of that commercial at the same time. Regarding your first comment, I would say that people who own flaslights don’t use them to scan other people’s property with any frequency either.
January 4, 2010, 3:26 pmChris Travers says:
I think it would be a search.
January 4, 2010, 3:30 pmIdgaf says:
Orin,
It seems to me that Kyllo is better read as reserving, or nominally reaffirming on stare decisis grounds, the question of how general public use affects the fourth amendment analysis to a later case. Footnote 6 says:
.
Scalia doesn’t exactly offer a strong defense of the public use prong of the test in the body of the opinion either, but instead inserts it as a caveat to other statements in the opinion. That would be consistent with language trying to limit the holding to the facts of the case, which indisputably include that thermal imaging devices weren’t commonly used(or in “general public use”) at the time Kyllo was decided.
In other words, I think the best answer over whether police can use thermal imaging devices now, what “general public use” means, or if public use is even a significant factor, is that it’s a close case, not squarely within the Kyllo holding, and deciding that would call for a more through grappling with the reasoning of Ciarolo and other cases.
January 4, 2010, 3:32 pmPatHMV says:
Whatever the outcome, it would be an interesting case, because the voting break-down was so unusual in Kyllo. Personally, I think that Kerr is reading too much into Scalia’s wording. My bet would be that Scalia would continue to find the activity in Kyllo to be a search even if one proved that 90% of the public owned such thermal sensors. But his opinion is an odd one, for him. Particularly in the section where he talks about Ciralo and how the “reasonable expectation of privacy” concept, initially developed to expand privacy protections to outside the home, has been used to reduce the 4th A. protection within the home, I would have expected him to discuss the danger of interpreting cases independently from the text of the Constitution itself, and to interject a cautionary note on Ciralo.
On the majority side, Souter was replaced by Sotomayor. On the dissenting side, O’Connor and Rehnquist have been replaced by Alito and Roberts. The voting blocs were distinctly not along traditional ideological lines, so it’s very difficult to say how the replacements might affect the outcome of a new case.
My bet would be that Scalia would prevail and use the case to expound on the dangers of court rules relying on such vague concepts as “reasonable expectation of privacy.” He might further say that in Kyllo, it was possible to reach the proper result without overturning a bunch of “reasonable expectation of privacy” precedents, and so he did so, but now that the technology in question has reached common usage, it is necessary to go further.
January 4, 2010, 3:36 pmOrder of the Coif says:
People STILL have a reasonable expectation of privacy re these devices.
It’s like using a microwave microphone to listen to conversations in phone booths or through living room windows. You can buy them at Radio Shack but that doesn’t mean your neighbors “expect” you to eavesdrop just because you can.
The public GENERALLY does not use these thermo imaging devices to scan other people’s property without consent. That use certainly isn’t “accepted.” It doesn’t merely facilitate one’s existing sensory input like a camera lens, it ADDS or EXTENDS a person’s ability to invade the privacy of another. For most folks, that’s a big difference.
January 4, 2010, 3:44 pmSW says:
I would suggest that what the court might mean by general public use, is whether the subject of the search (a part of the “public”) uses the technology to disclose information to the public, or the subject uses such technology in a way that disregards private v. public.
So internet camera’s in a person’s home can provide probable cause. Or, taking the scenario back in time, floor to ceiling window technology (sans drapes) can provide probable cause.
January 4, 2010, 3:44 pmAssociate man says:
Two points:
1) There is a significant difference between single point thermometer and a thermal imaging camera. The former are cheap and readily available, the latter are extremely expensive and not nearly as common.
2) I think it is extremely clear that the mere **ability** to purchase a thermal imaging does not equate to its “general” use.
In fact think the relevant issue for a 4th amendment analysis is this: ****”How often are FLIR thermal imaging camera’s pointed at the average person’s house?”**** (Or, put another way, is it at all reasonable to fear that my house will be hit with a FLIR camera tonight?)
Flashlights, headlights, and even zoom cameras are commonly pointed at people’s houses.
I don’t know ANYONE who has EVER had either an IR Thermometer or a FLIR thermal imaging camera pointed at their house. Until people are regularly walking their dog with such devices (or at least, until the paparazzi regularly use such devices on the homes of celebrities) I do not think their use should be considered “general”. Thus, I think police should be barred from using them under Kyllo.
(Finally, on a somewhat side note, I do not see how a single point thermometer could yield sufficient evidence to further a police investigation. Maybe… if pot is grown at a very specific temperature (is it?) a sensor could show that a room is at that exact temp? Otherwise, it seems absurd that the cops would consider it “evidence” that I like to keep my house at 82 when my mom likes her house at 72…….)
January 4, 2010, 3:46 pmJohn says:
It seems to me that the approach the court used in Kyllo is one of distinguishing between searches done by ordinary citizens and more invasive ones allowed by the police. Ordinary citizens can fly over your home and see what is in your back yard. They can use flashlights to look around your front yard. However, they cannot break into your house and search through your closet without your permission. The police may do so if they have a warrant. Instead of focusing on whether the technological availability has changed, the court is looking at how citizens behave and then drawing the line between what ordinary citizens and police can without a warrant, and what only the police can do with a warrant.
In practice, its not uncommon for people to look at their neighbors front or back yards. (Playing catch, ball goes over the fence, look for it, etc.) It is uncommon (so far as I know) for people to use thermal imaging devices on their neighbors.
January 4, 2010, 3:49 pmMark N. says:
For the people disagreeing with Orin on policy grounds—worried that such a result would produce less privacy and more police surveillance—isn’t that going to be a problem even if the police are prohibited from using the technology? If indeed these devices get into “general public use”, where anyone can IR-see inside your house from the street, it will be exceedingly hard to hide anything that can be easily uncovered with an IR device.
In the case where they’re used to look for drug-growing activity, a local anti-drug organization could simply drive up and down the street with the device, and then tell the police what they found. As long as the police didn’t actively induce them to do so (e.g. pay them) this wouldn’t count as a “search” under existing doctrine, which holds that private parties uncovering information and then voluntarily turning it over to the government isn’t a 4th-amendment violation, even if that search performed by the government would be (I believe Orin has an article on that somewhere, too).
So it seems, to me at least, that the privacy problem is with privacy-eroding devices getting into “general public use” in the first place.
January 4, 2010, 3:52 pmOren says:
It’s pretty common up north come winter as a handy way to figure out where your house is leaking the most heat.
Which might swing the entire thing! SS was not a strong liberal pick in the civil-liberties dept.
January 4, 2010, 3:54 pmRr says:
I wouldn’t draw that conclusion from Katz, provided that the conversation happens in public. Not that I necessarily agree the police should be able to use them, but it seems quite different to me. Same with the thermal imaging versus something like “through the wall” scan (although the thermal imaging is certainly also pushing the limits of my comfort with surveillance.)
On a related note, however, I find the use of the term “sensory enhancement” to describe thermal imaging a bit problematic. To me it’s “sensory augmentation” or “sensory supplementation,” a distinction which could provide some basis for comparing, let’s say, a telescope to an x-ray imager and a simple directional mic with amplifier to a laser mic. One lets you do something better, the other lets you pass a barrier you couldn’t overcome without close physical proximity or entry.
Of course, one could sidestep the whole thermal imaging issue by convincing Google to add IR imaging to its street view service … but all joking aside, IR imaging satellites may already provide enough promise there. Wonder if thermal imaging is a lost battle in the privacy war.
January 4, 2010, 3:54 pmOrin Kerr says:
Associate Man,
How often does a private airplane fly at 1,000 feet over your property and then look down to see what you are growing in your backyard? I don’t think I know anyone who has had that happen to them. But that doesn’t matter under the Fourth Amendment, based on the reliance on California v. Ciraolo in Kyllo.
Also, how do you know that no one you know has ever had their home pointed at with an IR thermometer or imaging device? I suspect you’re quite wrong about that, but I’m curious how you think you know that.
January 4, 2010, 3:56 pmAssociate man says:
Well, I live near Hawthorne Airport in Los Angeles so I have small planes over my backyard at least 100 times a day, many of them at an altitude where I could almost see the pilot’s face without optics and I could probably recognize a friend with optics.
And living in Los Angeles, we don’t use such devices on our homes. I am huge gadget nerd, I have all sorts of sensors and portable electronics most people don’t have (going to buy an AED next week). Despite my obsession with gadgets, I have never heard a single friend discuss IR scans of houses and I have never considered it myself.
O.K., when you say it is common to scan houses in the North East, do you mean that you hire companies with the $2000 scanners who come out, scan, and then do insulation work? Because that process (you have advance warning, and choose to have the scanner pointed at your house) seems very different than some stranger or even a neighbor scanning your house on a random day…
January 4, 2010, 4:04 pmseth says:
interesting stuff,
January 4, 2010, 4:06 pmand while i apologize for going back to the back to the tangential, i wonder whether the fact that growers tend to use flourescent lights these days would effect the interpretation here?
Anthony says:
While remote thermographic measurement isn’t an everyday occurrence, I have trouble seeing how it’s less common than flying overhead at 1,000 feet; I could (personally) certainly arrange for the thermal scan far more easily than I could arrange for the low altitude flyover. Thus, if reasonable expectation of privacy doesn’t apply to the low altitude flyover, it’s hard to see how it applies to thermal sensors.
I am unconvinced that I shouldn’t have a reasonable expectation of privacy in a back yard with reasonably high opaque fences (but no roof), but Kyllo obviously disagrees.
January 4, 2010, 4:07 pmJeff J says:
Why doesn’t the court just adopt this bright-line rule: Any use of a device that allows police to discern facts about the interior of your home or curtilage that they would be unable to learn through the use of their unaided senses is a search?
January 4, 2010, 4:07 pmEMB says:
Just because something only costs $100 doesn’t mean it’s in general use (and could you really do this from the street without the $2000 model?); personally I’d never seen anyone use any of these devices, and so before reading this post I would have had no idea the police might be able to do this.
January 4, 2010, 4:11 pmJoeSixpack says:
I don’t know, if some stranger or even a neighbor was scanning my house with a flashlight on a random evening I would find that highly unusual.
January 4, 2010, 4:12 pmJeff J says:
A couple other points:
1) Kyllo’s airplane analogy doesn’t exactly fit, because using an airplane doesn’t augment/amplify the senses; it just gets the cops closer to your property so they can see what’s in your yard.
2) What if most state legislatures passed laws prohibiting private citizens from using thermal imaging devices on other people’s residences? What if people routinely did so anyway? Could legislation on public use change the analysis of whether the use is “general”? If not, is there anything to stop technological advances from whittling away privacy expectations for 4th Amendment purposes?
January 4, 2010, 4:15 pmOrin Kerr says:
Associate Man, the “Oren” who said “It’s pretty common up north come winter as a handy way to figure out where your house is leaking the most heat” wasn’t me. I’m Orin, not Oren.
As for how you know no one you know has been scanned, do you have any friends who work on their own cars? Are you sure that they don’t have them?
But in my experience, the single point thermometers that you buy for $50 do the same thing the $2,000 ones would do, at least if you have the patience to spend a few minutes to scan rather than demand an instant scan. (Note that the scanner in Kyllo took a few minutes anyway).
January 4, 2010, 4:20 pmOrin Kerr says:
Jeff J.,
Re #2, the Supreme Court rejected that in California v. Greenwood. See also Virginia v. Moore.
January 4, 2010, 4:21 pmAssociate man says:
Again, I think the threshold issue is “How often is a thermal imaging device pointed at a private home without the prior knowledge and consent of the occupant?”
I take pictures of people’s houses around LA on a weekly basis as a hobby. I know or know of 100s of people who do the same. I talk walks at night and point my flashlight at intersting houses and cars and pathways.
I have never heard anyone say “I am going to IR that guy’s house tonight!!”
Edit: I apologize for the mistaken identity and also my breathless tone.. I get so excited so easily on the internet! I do love the intersection of gadgets/tech and law. Want to offer me a fellowship and save me from my shitlaw job? :)
January 4, 2010, 4:24 pmDavid Schwartz says:
Sure, by a simple mechanism — technology changes what expectations are reasonable. You’re talking one very short phrase completely out of a context that says the exact opposite.
The phrase “at least where (as here) the technology in question is not in general public use” does not change the meaning of every other word around it. It says that in the case where the technology is not in general public use, it is definitely a search to obtain information that could not have been obtained without physical intrusion. It does not say that using technology in public use is immune.
And we have the test for when it is okay and when it’s not — it’s a search if it violates an expectation of privacy that is accepted as reasonable. Public use of new technologies changes the equation by eroding that expectation.
Those five words in Kyllo did not create a whole new standard for what constitutes a search.
January 4, 2010, 4:31 pmLucius says:
Is there a constitutional argument that the visible spectrum of light emanating from a house is unprotected, but ultraviolet and infrared spectra are?
From the scientific view, I find it hard to believe that people have ownership of the photons that leave their property, regardless of whether they are in the visible or extra-visible spectra.
January 4, 2010, 4:31 pmPerseus says:
I have never heard anyone say “I am going to IR that guy’s house tonight!!”
That was the point I was going to raise. Did the Court mean by “general public use” that the technology would simply have to be widely available, or did it also mean that the public would use the technology in a similar manner such as those mentioned by “Associate man.”
January 4, 2010, 4:31 pmBuddy Hinton says:
Kyllo uses its availibility-of-the-hardware test as a way of ducking the more fundamental problem, which is that probable cause evidence is often incompetent and there is not a good way to challenge that lack of competence later in a suppression hearing (where it is invariably the case that the putatively incompetent evidence just so happened to be correct).
Pity the poor magistrate. The policeman emails in an application that says: “I found a hot spot — I have probable cause.” What to do? How is the magistrate to have the faintest idea whether a hot spot means that there is more or less than a 50% chance that contraband is there? Who has studied this? Do you just trust the “policeman’s training and experience”? Has the policeman kept any written records of how many hotspots were fruitful, and how many fruitless? Of course, the concern is that some magistrates will just roll over and sign because it is difficult, as a practical matter, for an innocent searchee to challenge a warrant like this for incompetence. It may even be impossible.
Which leads us to the correct answer to Professor Kerr’s question:
How widespread does the use have to be? Use of heat imaging should be so publically widespread that it has become common, judicial-notice-style knowledge of how strongly a hotspot corresponds to a grow op. If someday becomes common knowledge that hot spots almost always correspond to grow ops, then, at that point in time, and only at that point in time, should we let police use the technology on a warrantless basis. If someday it becomes “consencus” knowledge (by more tan just policemen, mind) that hot spots very seldom correspond to grow ops, then, at that point in time, and only at that point in time, should we let police use the technology on a warrantless basis. There is no sense in allowing the police to use a technology like this until magistrates have a reliable, independent (of the policeman) basis for evaluating the results. The “widespread public use” requirement can and should be used to enforce this sensible policy as against policemen and popofriendly magistrates.
January 4, 2010, 4:34 pmMike McDougal says:
“General public use” strikes me as the wrong test in the first instance. It seems to me that the general public’s increasing ability to invade my privacy through technological searchese shouldn’t increase the government’s latitude to invade my privacy.
January 4, 2010, 5:06 pmPhelps says:
I think general public use has to include actual use for this purpose, not simply availability. If that were the standard, since x-ray machines are in general use in hospitals for medical imaging, it would be okay for the police to use a fluoroscope on your house to look inside. I think it would also have to be something that is in general use on the property of others, since, for example, power drills are in general public use, and are even used to drill locks, but that does not allow the police to drill the lock on your house to take a look around.
January 4, 2010, 5:09 pmSoronel Haetir says:
One question I have on this topic and the devices brought up in the original post. How if at all is the analysis changed by the fact that many inexpensive digital cameras sense IR? It’s not calibrated the way the mentioned devices are but an enterprising user could likely work out a reasonable conversion.
January 4, 2010, 5:11 pmChris Travers says:
Here you are shifting from what people CAN do and what they actually do. The average person doesn’t cruise around his neighborhood looking for people who are speeding, but that doesn’t mean police can’t.
It seems to me that if you draw the line around what ordinary people are permitted to do then if I am permitted by law to point a FLIR imager at my neighbor’s house, then the police should be permitted to do the same at my house, whether or not people do this.
I am not entirely sure that this line works. The basic problem is that it holds the individual privacy and liberty hostage to the development of high-tech devices. This was the problem the court seems to have tried to get around in Kyllo. However, Kyllo seems like only a very small part of the solution.
January 4, 2010, 5:11 pmOrin Kerr says:
David Schwartz,
You have an interesting theory about what Kyllo should mean, and perhaps you should write it up as a law review article. However, in this post I am assuming what I believe is the more common (and correct) understanding about what Kyllo means. I realize you disagree with it, as you often disagree with my views of Fourth Amendment doctrine, but let’s assume it’s the case for the purposes of this post.
January 4, 2010, 5:12 pmMike McDougal says:
You can also do that with a reflected laser and a photo sensor.
January 4, 2010, 5:14 pmDennis N says:
Looking at the “In common use” criterion, it seems to make a certain amount of off the cuff sense. This particular technology may be the ideal example.
Let’s say that infrared night vision devices become dirt cheap. You could by “IR Driving Goggles” or “Coon Hunter’s Glasses” for fifty bucks. Similar systems are already marketed with some luxury cars, so I’m not too far off base, here.
Now, if you look out your car window, or walk down the street, you can see whose roofs “glow in the dark.” It is something that would be much more casually noticeable than bushes with the wrong shaped leaves, out on the back fenceline. Do you have any reasonable expectation of privacy against glowing in the dark?
January 4, 2010, 5:14 pmAnym_Avey says:
How often does a private airplane fly at 1,000 feet over your property and then look down to see what you are growing in your backyard? I don’t think I know anyone who has had that happen to them. But that doesn’t matter under the Fourth Amendment, based on the reliance on California v. Ciraolo in Kyllo.
In point of fact, the average citizen can and regularly does do nearly that, and can be enabled to do so even from his or her living room, using Google Earth. The imagery is admittedly delayed, but no warning is given as to when a new image might be captured and uploaded into the Google servers, so short of covering all of your yard in a camo canopy, the satellite could capture anything which Google might make freely available to the public some time later.
In and around dense urban areas and popular attractions, the resolution is high enough that an amateur botanist could pick out many species of trees, merely by knowing a little about the climate and observing the tree’s foliage and shadow pattern it casts on the ground. That’s not very far at all from being able to count five leaves on a suspicious-looking fern; one more level of resolution will probably get us there.
January 4, 2010, 5:29 pmMike McDougal says:
If I had to define “general public use,” I wouldn’t look at price points or retail availability. There are free things that aren’t in “general public use.”
My naive reading of the term is that a technology is in “general public use” when the average member of the public is aware of the existence of the technology, is aware of its capabilities, and is aware of its ubiquity.
January 4, 2010, 5:56 pmAnym_Avey says:
Pity the poor magistrate. The policeman emails in an application that says: “I found a hot spot — I have probable cause.” What to do? How is the magistrate to have the faintest idea whether a hot spot means that there is more or less than a 50% chance that contraband is there? Who has studied this? Do you just trust the “policeman’s training and experience”? Has the policeman kept any written records of how many hotspots were fruitful, and how many fruitless? Of course, the concern is that some magistrates will just roll over and sign because it is difficult, as a practical matter, for an innocent searchee to challenge a warrant like this for incompetence. It may even be impossible.
Read the linked item at Findlaw and go back through the case history. The warrant was issued on the basis of the thermal imaging (which was presented in comparison to the two adjacent homes in the triplex structure, at an unlikely time of night), evidence from utility bills, and evidence from multiple informants. The warranted search then turned up a substantial quantity of marijuana plants in the suspected location. The only thing particularly novel was the use of the (grayscale) infrared camera to add to the probable cause, which it might be noted, was done in 1992, rather early in the life of such devices.
The 2001 ruling was simply the time it took to walk the case all the way through to SCOTUS.
January 4, 2010, 5:59 pmAnthony says:
For the way modern digital cameras work, not at all — they’re sensitive in near IR, not long-wave (thermal) IR, which means they aren’t useful for identifying temperatures much below the point where the object glows visibly red. Obviously, this might change in the future — you can buy FLIR systems for cars (intended for detecting animals and pedestrians at night, outside of headlight range), and I can easily see that becoming extremely common in the relatively near future.
January 4, 2010, 6:14 pmBuddy Hinton says:
Lets be clear. I am not saying that a warrant should not issue if there are enough informants and they are reliable enough. I am saying that a magistrate should not be put in a position to have to judge whether or not thermal imaging enhances probable cause, at the margin, until a magistrate is really in a position to have a decent quantitative handle on this issue. (I would actually say the same thing about utility bills.)
If the Kyllo warrant could have been obtained without the thermal imaging then that is what the policeman should have done. If the warrant in Kyllo would not have obtained with thermal imaging, I think it was wrong for the magistrate to have considered it. Ideally, we could punish the magistrate for performing her duties badly. Back on planet USA, the best practical solution was to do what the Court did and say that these things are not in common enough use to be useful yet.
January 4, 2010, 6:14 pmDMZ says:
This legal debate will matter less and less as marijuana growers adopt LED lights: http://www.homegrownlights.com/WhyLED.html .
January 4, 2010, 6:17 pmDr. Caligari says:
I propose we use the :”What the hell do you think you are doing?” test in this matter.
For example, if you are standing on the street looking at my house or taking a photograph of it with a conventional camera and I see you I’m probably not going to do anything about it, at least if you don’t linger there too long. So anyone can come and stare at my house from the street for a few minutes or take a picture of it.
If, by contrast, I see you using binoculars to look through my windows and see a level of detail of things within the house not visible from the street to the naked eye, or using an obvious high-power telephoto lens on your camera to make photographs of the same and I see you I’m going to come out and say “What the hell do you think you are doing?” The fact that the behavior may be technically legal isn’t going to prevent me from letting you know that I think your behavior is grossly inappropriate and making sure that anyone passing by is aware of my opinion.
Likewise if I see you doing thermal imaging of my house I’m going to confront you. That isn’t expected behavior any more than staring through windows with binoculars.
January 4, 2010, 6:21 pmAndrew says:
Justice Scalia made some amusing remarks about the Fourth Amendment last summer. Click here, and search for “lobby.”
January 4, 2010, 6:22 pmSteve P. says:
Also keep in mind that an infrared imaging device is substantially different from other devices mentioned in this thread — it is purely a passive device, and doesn’t “intrude” in any meaningful way, other than your conclusions about the data it presents. At least, that’s how infrared thermometers work, and I believe these hold to the same principles.
Infrared guns measure emissivity, specifically the infrared light given off by people/buildings/rocks/etc. In contrast, a number of the other devices mentioned as comparable to the infrared gun actually use the Doppler effect — bounce microwaves off of something, and measure changes in the signal when it returns. Hell, even a flashlight is more intrusive, since it bounces lightwaves into a dark place that police might be otherwise unable to enter.
Obviously, this isn’t a difference in the legal sense, but I wonder if that kind of “intrusive” factor plays into future 4A decisions.
January 4, 2010, 6:22 pmDavid Newton says:
This gets to the heart of a fundamental weakness in the ratio of Kyllo which is completely unrelated to the widespread use test. All photons are fundamentally the same: all that varies is the wavelength. Where is the wavelength limit for a search and what determines it? So far as I am concerned, if something leaves the curtilage of a dwelling then it is fair game for the police. In the same way that trash awaiting collection is fair game then any emissions of sound or light which can be picked up from across the street or even from the sidewalk outside are fair game. If a police officer overhears a heated argument when they are walking down the street outside a house is there anything stopping that argument being used as evidence against someone in a criminal trial? In the same way if someone leaves a cannabis plant growing outside in their front garden which is visible from the street and a police officer notices it whilst walking down the street outside the house is there anything stopping that cannabis plant from being used as evidence against someone in a criminal trial? If there are then there should not be. Things which are viewable or audible from the street have left the setting of private and crossed into the setting of public. It does not matter what wavelength that light or those sounds are at.
There are certainly policy arguments for setting a limit on the signal to noise ratio of equipment etc to make sure that warrantless searches cannot pick up too much detail, but that is an entirely different argument than the ratio in Kyllo. It is also a quantifiable and logical test. The other restraint on the police which has strong policy arguments is the prevention of the dropping off of bugs without warrants. Whilst there is no reasonable expectation of privacy for a conversation when someone else is in earshot when that person is out of earshot then there certainly is. There should be a requirement for the police officer to be physically present for any warantless searches.
January 4, 2010, 6:45 pmOrder of the Coif says:
Reasonable “expectation” must be narrower than whatever is physically possible. And narrower than whatever private citizens CAN do. Otherwise the test is meaningless — if you can, you can.
There has to be an element of regular ACCEPTANCE as a risk of life in a crowded society. We accept that people walking by on the street can use their eyes to see into our outside yard and even into our uncovered windows. That’s not the same as using one of the new millimeter wave scanners to pry (yup, that’s the word) into your bedroom. We risk invasions that Society widely (80% ???) accepts but we do not “risk” (the flip side of “expectation of privacy”) everything that is physically, mechanically possible no matter how widespread the technology.
I think the key question relates to acceptance as a way of non-consentual information gathering.
And, secondary to that, how do we determine acceptance? The personal opinion of the judge or justice in question? Or maybe surveys of what the real people believe? We have the survey technology properly utilized to seek out more than the opinion of 9 old men and women, shouldn’t we use it?
January 4, 2010, 6:48 pmBuddy Hinton says:
Unless of course they invent photodetectors that can detect small amounts of visible light that typically leak through walls which have very bright LEDs behind them. Then the cycle starts anew (but hopefully against a more sensible jurisprudence backdrop).
January 4, 2010, 6:48 pmPhelps says:
So where does that end? Let’s go with a thought experiment. Let’s say that a device was created that detects cosmic rays passing through the house and how they are deflected, and can put those together like a backscatter x-ray to let someone using the device literally see through walls and get a radar readout of every inch of the house, inside the walls, behind any sort of doors, even in the bodies of the people in the house. Would the police be allowed to use that? If they were, how could the people inside be considered to be “secure in their persons, houses,” etc? Nothing is being “beamed” at the house, because it just uses background cosmic radiation. It’s all detectable from the street.
And then, if we climb that hill, how about if it is detectable from 1000 miles away? What is an operator in Washington can scan the entire eastern seaboard from his desk?
January 4, 2010, 6:53 pmTweets that mention The Volokh Conspiracy » Blog Archive » Can the Police Now Use Thermal Imaging Devices Without a Warrant? A Reexamination of Kyllo in Light of the Widespread Use of Infrared Temperature Sensors -- Topsy.com says:
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January 4, 2010, 6:55 pmanomdebus says:
I think a better gauge of “expectation of privacy” would be how widespread means of shielding against that surveillance is. After all, people are aware that if they stand by windows, they can be seen from the street, hence curtains and blinds. Back yards can be spied upon, hence fences and hedges.
I have wondered whether certain paranoid tinged movies don’t have a part in the erosion of privacy, presumptively against the view of the creators. (for example) Based on movies, people may expect that based on a cell phone call, someone can train a satellite onto them in order to read their notes from space. Even if it is not possible now, it may be and the public has already been softened into thinking it is possible. (Note: I am talking about no delay, any point on earth surveillance, not “wait until the satellite clears the horizon and can pick out the right car” surveillance.)
January 4, 2010, 7:11 pmI suppose it works both ways though. CSI-like shows have popularized how little can be used to solve a crime and their methods are not supported by whether the public believes it or not.
Kharn says:
You can’t refuse consent to the cops pointing a scanner at your house, but you’re free to stay home from flying.
January 4, 2010, 7:14 pmPaul Allen says:
Orin: you seem to be raising a compound question in asking whether Kyllo is still good law.
1) are search by thermal imagers now exempt
2) is the general rule announced still valid in regards to other technologies
3) is the legality now uncertain
January 4, 2010, 7:15 pmMike McDougal says:
Humans can only detect some of them with their natural senses. And what people can detect seems to be the heart of “searching.”
January 4, 2010, 7:15 pmMike McDougal says:
That’s detectable by natural senses, which I think draws a reasonable line.
January 4, 2010, 7:18 pmOren says:
While you are drafting the legislation, why not just explicitly require the police to get a warrant to use thermal imaging device? The legislature is well within their (its?) powers to regulate the police in excess of the strictures Constitution.
January 4, 2010, 7:37 pmJeff J says:
Fair point.
January 4, 2010, 8:06 pmjccamp says:
I think Chris Travers has captured it correctly. If any citizen can lawfully, using a commonly available gadget, walk or drive down the street and obtain some data, then probably the cops can do the same thing without a warrant. I’m not sure I knew or even cared about the existence of these things, so I can’t say if they are in general public use. I suppose there would have to be a hearing on the factual question – the resultant decision probably subject to the pre-existing opinions of the trier of fact about the underlying issues rather than the “general public use.”
However, I suspect that thermal imaging devices – at least those available to the government and TV detectives – can show a lot more than gross areas of heat and non-heat. So there probably needs to be some refining of the original decision to reflect the additional capability, which definitely would intrude upon the privacy of a home.
But I repeat, reducing the original decision to some everyday standard that cops might use, if citizens can legally and lawfully, using a commonly available device, obtain some data or view something with the senses, than probably a cop can do the same thing without a warrant, absent some specific statutory requirement. So, if the typical thermal devices as described could report the temperature variants on a house sufficient to indicate a marijuana grow house area, then yes, I’d say the decision would now allow for the cops to do so.
January 4, 2010, 8:12 pmjccamp says:
But I don’t think I’d risk a major violator to find out if I was correct…I’d perhaps urge some other agency to be the pathfinder on this one.
January 4, 2010, 8:14 pmKirk Lazarus says:
As a libertarian I find the idea that individuals have some sort of property right over the EM emissions they send into the pubic domain or other persons’ private property is absurd. If you think they might reveal something about you that you don’t want them to know, improve your shielding.
January 4, 2010, 8:15 pmIf anything it is the building industry that is at fault. Walls are there to protect our privacy (among other reasons). If thermal IR sensors are common then walls with thermal IR shielding should be standard.
jccamp says:
Oren is absolutely correct. There is a statutory remedy which removes the uncertainty for everyone, including law enforcement. It wouldn’t have to address private parties, only the use of such scanners for search warrant affidavits.
January 4, 2010, 8:16 pmt1 says:
Is “because it’s easy and cheap to do” a good rationale for determining whether something is not a 4th amendment violation?
You can obtain equipment for under $100 to clip onto phone lines to tape calls. It’s cheap and easy for the police to sneak into your house and look through your papers when you’re not there. (Yes, the explicit protection of papers in the 4th Amd. moots this, but the fact that “cheap and easy” didn’t enter into the drafting of the 4th Amd. suggest to me that Kyllo rationale is incompatible with it.)
January 4, 2010, 8:40 pmt1 says:
Aren’t cellular telephone signals and e-mails also sent out into the public domain over the airwaves?
January 4, 2010, 8:41 pmShelbyC says:
Of course, that’s true for the whole scope of the 14th amendment.
January 4, 2010, 8:55 pmAnthony says:
Walls with IR shielding are quite common, they’re just called ‘insulated’, on the grounds that most people care more about their heating/cooling bills than whether people might be trying to look through their walls with IR scanners.
January 4, 2010, 8:56 pmGaryC says:
In addition to the specific Supreme Court cases that OK mentioned, the phrase “unaided senses” is too broad, since it might be interpreted as disallowing the use of eyeglasses or contact lenses.
Note that there are hearing protectors used by hunters that limit the volume of sound when a firearm is fired but amplify lower levels of sound. There are at least hundreds of thousands, possibly millions, of these devices in use. Hunters are clearly more likely to fire a weapon on a given day than a police officer, so they need the protection more, but hearing damage from gunfire is an obvious health hazard for police officers. At a firing range they can wear passive protection, but any hearing protection that limits hearing while on patrol would be unacceptable.
So should the average cop on the street be issued these amplified hearing protectors?
If so, can he testify about the content of low level conversations that he could not have otherwise overheard?
January 4, 2010, 9:11 pmJohn Moore says:
Off topic but the engineer in me can’t resist:
Those devices are, by definition, not imagers. They are bolometers. Imagers produce images.
On topic:
To this non-lawyer, it appears that using sensory enhancement to detect the contents of houses is a violation of the 4th. Period.
January 4, 2010, 9:12 pmanomdebus says:
Kirk,
Your reasoning would make perfect sense if the cameras are passive. Is this the case?
In an absurd example where the visible spectrum is protected so no one was allowed to even look into another persons property, I don’t think anyone would say that passive (as in “ow that’s hot”) detection of heat from a fire across property lines would qualify as invasion of privacy.
January 4, 2010, 9:26 pmjccamp says:
John Moore -
I think the typical thermal devices – whatever we term them – do not detect contents, human, plant or mineral. They just measure temperature gradients, right? A good operating theory is that anything a law-abiding civilian can see or sense, from a place where he/she is legally entitled to be, is fair game for the cops, absent some specific statutory restriction.
So, if you can take your thermal device, stand on the sidewalk and point it at the neighbor’s house and see that he/she has an abnormal hot spot indicative of higher than normal heat, and an inference can be drawn based on that fact (and probably other supporting and consistent facts) that the high heat is predictive of a marijuana grow house, then how can you tell a cop he/she can’t do the same thing any ordinary civilian can do. That’s counterintuitive.
If the thermal device actually defines objects or persons, then I think there would be no question, using a device would be a 4A violation without a warrant.
An example: There was at one time, some freedom on wireless/cordless – not cell – phone conversations (for warrantless police interception), under the theory that it you used one, anyone could intercept your calls and listen with a common scanner or another base station. If John Q. Citizen can do so, so can law enforcement. However, as in many forms of wireless communication, there are specific laws which govern the use of intercepted conversations and specific procedures for law enforcement to follow. Although I believe that common, commercially available scanners which intercept cell calls are no longer available (at, say, Radio Shack) like they once were, even if you have one, it is not longer lawful to use it for that purpose.
Personally, I’m not sure how much a threat a marijuana grow house represents in the scheme of things, so I’m not really vested in this debate. I’m just offering my opinion about what the original USSC case says and means. And I’m probably wrong anyway…
January 4, 2010, 9:32 pmMike McDougal says:
That’s detectable by natural senses.
January 4, 2010, 9:39 pmjccamp says:
Shelby –
I was suggesting a statutory remedy as a path away from allowing the courts to decide on some ever-changing definition of what is or is not permissible, based on the inventory down at the Radio Shack. If sufficient people don’t like the idea (of thermal scanners), there is precedent for simply writing the method out of the (search warrant) game. Some of this occurred back when there was a temporary overlap of available radio scanner capability and cell phone broadcasts. In time, technology took care of the issue by creating an expectation of privacy. In this case, I suppose it would have to be instant home insulation or something, tin-foil wall paper, I don’t know.
Confusion in defining the limits benefits no one. This looks like a moving target to me, and hence, bad.
January 4, 2010, 10:52 pmOren says:
Yes. You are free to listen in on my WiFi from the road or tune your radio to my phone’s frequency. Alas, modern encryption means you won’t be able to suss anything decent out of it without convincing/coercing either me or the various third parties (phone company, email provider) into helping you out.
January 4, 2010, 10:55 pmOwen H. says:
The analogy between using IR imagery and an airplane flying overhead is ludicrous on its face, Flying over, they can see exactly what is there, from public airspace. A “hotspot” in a scan does not tell them what it is. Declaring it to be “evidence” of illegal activity is on par with declaring that the fact that I have long hair is probable cause to search me for drugs. Or that the fact that in the fly-over they decided that your covered patio proved you were hiding illegal activities under it.
January 4, 2010, 11:11 pmOren says:
They do not detect gradients, they detect absolute temperature.
What exactly is your definition of “good operating theory” here?
Persons, yes. Objects, no. Actually, not sure what you mean by “define”. You can certainly pick out a person against the background. See, e.g. this video starting around minute 5 – there is clearly a single individual that is well defined, legs and all.
Now, if that’s what you can do from thousands of feet away …
January 4, 2010, 11:13 pmOren says:
Owen, the police do not need “evidence” of a crime to get a warrant (that would be rather circular, since a warrant is issued to search and seize evidence), only probable cause — a much lower standard. An attic that is 100F for 18 hours a day and 70F for the remaining 6, on a strict schedule, leads to the inference that there is probably a grow room in there. Combine that with some other easy observations (high power/water usage), lack of apparent tenants, undocumented or straw-man lease and you’ve got unimpeachable PC.
That is, even if the IR evidence is not PC of itself, a warrant application is viewed on the totality of the evidence, not by looking at each piece in isolation.
January 4, 2010, 11:24 pmanomdebus says:
Mike,
January 4, 2010, 11:33 pmMy admittedly absurd example was referring to Kirk’s apparent suggestion that this is necessarily about protecting the infrared radiation that crosses property lines from examination.
Oren says:
That’s entirely irrelevant to the case at hand though, since a warrant is the rule only for a search and the government’s contention in the case (as well as Illinois v. Caballes or California v. Ciraolo) is that no search took place in the first instance. It is well conceded that if what happened in Kyllo was a search then it was certainly an unlawful search — there is no need to continue on about warrants.
A good place to start might be the opinion itself where Scalia discusses the interplay between the warrant rule and the delineation of what constitutes a search (my emphasis):
It’s a rather insightful comment into how the Court actually makes law — if one expands the definition of what constitutes a search then one has to contract the warrant requirement in order to fit in ‘searches’ that ought to be legal without a warrant. The Court has (quite wisely, IMO) chosen to contract the definition of the search rather than the more dangerous approach of carving out exceptions to the warrant requirement.
January 4, 2010, 11:37 pmRicardo says:
The point of Kyllo though was that this is not the correct consideration to use. If it was, it’s not clear where this leaves all of our precedents on wiretapping which can be done by measuring electromagnetic fields on public property. I’m not an engineer but isn’t it already possible to capture and magnify residual sound waves outside a person’s house (perhaps through a window pane) to record conversations? I’m quite sure surveillance equipment can allow one to capture images from a person’s computer screen by analyzing electromagnetic waves. Sophisticated thermal imaging devices can detect and track human bodies and so could tell you all sorts of information about what people are doing inside their homes. Increasing reliance on cell phones, WiFi and Bluetooth increase the possible scope of surveillance even more.
I’m not a lawyer so I don’t know where exactly to draw the line but it does seem to me that technological progress means that if we limit the 4th Amendment to physical intrusions in the home we make Big Brother-esque spying on activities inside the home virtually inevitable.
January 4, 2010, 11:39 pmFederal Farmer says:
I was using those devices in my own home pre-2000, but perhaps that isn’t common considering I had a basement full of reptiles and amphibians. Some of my desert lizards required basking temperatures of 110 to 120 deg F.
I’m sure my electricy usage and my temperature signature would have set off warning signs. Thankfully my doors did not get kicked in!
January 4, 2010, 11:41 pmRicardo says:
For one thing, it is part of the original meaning/understanding/intent of the Fourth Amendment that it protects the home from warrant-less searches. As a non-lawyer and non-4th-Am-scholar, it’s less clear that the original meaning/understanding/intent was to protect people in public places from warrant-less searches or if it did, that the protection afforded was on par with the protections afforded at home.
January 4, 2010, 11:47 pmOren says:
You know, quite often they knock. The image of warrant-service as a violent entry is entirely out of proportion to the small fraction of warrants actually served that way.
Trivial with a parabolic mic and some cheap equipment. More sophisticated versions actually shine a small IR laser at the window and measure the reflected beam — that has the advantage that you can set up on a building across town instead of the ever-suspicious-van parked right outside.
Most TVs, computer monitors and keyboards can likewise be ‘tapped’ passively from outside the house. Rumors have it that the CIA developed van-Eck devices that could do this from over a mile, although the actual details remain classified.
January 4, 2010, 11:51 pmNorman Yarvin says:
Not that it matters much as a point of law, but the $50 devices all have a very wide beam spread. That is, they measure the average temperature over an angle of something like 10 degrees. So even in theory, you can’t do high-resolution imaging by scanning the device. To get a narrow measurement angle, you need a device with a better lens, which costs several hundred dollars new.
In any case, the really invasive search modality is millimeter-wave radar, which can penetrate deeply and with high resolution. The Kyllo decision made it sound as if Scalia imagined thermal imaging to have the sort of invasive potential that millimeter-wave radar really does have, and got scared.
January 5, 2010, 12:07 amRicardo says:
That’s what I thought. I’ve seen this in movies but didn’t want to be caught making an assertion of fact based on a Hollywood movie.
January 5, 2010, 12:07 amFederal Farmer says:
Neither technology being in common use.
January 5, 2010, 12:12 amjccamp says:
“They do not detect gradients, they detect absolute temperature. ”
At least one of the models mentioned in the OP displays relative temps – gradients – that’s the commercial FLIR. Either method would probably suffice for a warrant, as long as the reading was compared and differed from some neighborhood observed average.
“…tune your radio to my phone’s frequency…”
Actually, intercepting private (wireless) phone conversations without consent or court order is now a crime, I believe, both Federally and in most states. Scanners now commercially available are no longer supposed to be capable of intercepting (U S) cell phone calls.
Good operating theory – Considering each of the 50 states are free to create statutory limitations more restrictive than the 4A, and the respective 50 state supreme courts are likewise free to interpret state constitutional rights’ protections in unpredictable ways, there is no One Size Fits All answer for some of these issues. The answers must be crafted to the jurisdiction. Considering also that lawyers and law professors will argue these points ad nauseum, courts will decide, rehear, be reversed, rehear en banc, etc for years, cops need some simple, common sense – I know, I’ve been told before: common sense has nothing to do with The Law – to guide their actions. Similarly, if as a layman, one wished for a simple rule, then perhaps a “good operating theory” would suffice. So, a good operating theory is just what I said: if any civilian can, while lawfully in a public place, sense something, then an officer can probably do the same thing without a warrant.
That work?
The device you’re referring to, a military grade thermal imaging device, is far different and far more intrusive – revealing – than the hand held temperature gauges or whatever these gadgets are that we’re discussing.
Owen –
As Oren pointed out, the presence of a hot spot does not, in and of itself, establish PC for a grow house. It is usually used as corroboration for other, independent sources, such as an informant. Other corroboration could include excessive power bills, phony names on leases, mail order deliveries of grow equipment, etc.
January 5, 2010, 12:14 amRicardo says:
But there does in fact need to be a one size fits all rule that constrains the FBI, DEA and other federal agencies. The Supreme Court explicitly considered and rejected the argument that a state anti-wiretapping statute meant that federal agents could not use the results of a warrantless wiretapping [back before it was considered unconstitutional] as evidence under the exclusionary rule. Only searches that are unconstitutional, not illegal, are subject to the exclusionary rule. And there is a large body of law that state law and state court decisions cannot impose additional restrictions on federal law enforcement.
I’ve seen Orin Kerr elsewhere be critical of the idea that the 4th Amendment or other parts of the Constitution should be re-interpreted in light of statutory laws. Sometimes, whether a technology is in “general public use” or not may depend partly on whether it is legal or not (as some of the advanced surveillance equipment I mentioned is probably not). If we consistently apply a “general public use” standard it may sometimes collapse down to a “are ordinary citizens legally allowed to use it?” standard which Prof. Kerr has I believe criticized elsewhere and which the Supreme Court appears to have rejected in its earlier wiretapping decisions.
January 5, 2010, 12:46 amPhelps says:
This is an absurd argument. No one is claiming copyright over the IR emissions of their house. This is about limiting government activity beyond the limits of the public, which is routine in libertarian thought.
January 5, 2010, 1:27 amDavid Newton says:
Some of the techniques which are discussed here clearly go into the realm of searches, where that term is used in its judicial meaning. For example firing a laser at a window and reading the results to reconstruct conversations going on inside that room would not come under my definition of something which can be done from the street passively. Perhaps I did not make that clear: what I meant by things leaving the curtilage of the house is things that can be acquired passively. That means no radar techniques or similar because those involve emission of radiation and then the picking up of the results bounced back. That is fundamentally different than passively scanning sounds and light coming out of the house.
There is an argument for limiting something to what can be picked up by the unaided senses, but that argument has been lost. Glasses and contact lenses have been used by police officers for a very, very long time and they augment the unaided senses. The same is true of hearing aids, although they have not been around for nearly as long. Consequently the argument is certainly not over the use of completely unaided senses. If that is not the case then the argument is over the degree of aid which is allowed for the senses. Does it stop at glasses or magnifying glasses or cameras? Does it stop at thermal imaging cameras which merely transform one part of the EM spectrum into another?
If the argument is over the degree of aid then what is needed is a proper objective test for that degree. The standard of Kyllo is clearly subjective and is poorly thought-out as the changes in the thermal imaging camera market over the last 8 years potentially causing a radical shift in the amount of evidence allowed to be collected without a search shows. Only allowing passive evidence collection would immediately rule out a lot of potentially troubling invasions of privacy. It would not solve all of the problems however, leading to the need to limit the resolution at which passive evidence collection can occur. I am not an expert in the field of remote sensing so I do not know a measurable way in which resolution can be so limited. However I am sure that such a measure exists, and in concert with a ban on active sensing being used it presents a consistent and watertight limit to warrantless evidence collection. As I mentioned in my previous posts, at a guess it would be something like a limit on the signal to noise ratio evidence could be collected at without a warrant which would be the correct measure.
Like eminent domain the current law in this area appears to be a mess, and that mess appears to be at least partially the result of a Supreme Court ruling in the area. In eminent domain the court did not protect the rights of property owners properly and in searches and court did not put forth a proper rational test. I am not sure whether in Kelo the court was actually following the wording of the relevant part of the constitution: its hands might have been tied. In this case the test of entirely of its own devising and consequently the mess is entirely of its own making.
January 5, 2010, 5:55 amBuddy Hinton says:
I have only ever seen one raid that was (probably but not absolutely certainly) based on heat imaging (in conjunction with an anonymous tip):
http://www.youtube.com/watch?v=EHmP_KtmcB4
Turns out it was a “reverse sting” on the police to check if they were being true to Kyllo. It does not appear that the door was kicked in, but what is scary is the utter lack of announcements as the police move through the house dressed like robbers. Maybe* the police knocked and announced before they entered, but if somebody inside the house had not made out the announcement it looks to me like a gunfight could very well have started because of the misplaced stealth when the police went room to room like home invaders, not dressed in immediately recognizable police uniforms. The “new professional” is a joke.
When the only real, honest-to-goodness heat imaging raid you see looks like this, it is really hard to take the reassurances, like the one you are making here, Oren, seriously. Got vids?
FOOTNOTE:
* watching the video as a whole I kind of doubt it.
January 5, 2010, 7:25 amAri Tai says:
How ’bout a thought experiment? Imagine we find ourselves with prosthesis (or stem cell replacement or …) that greatly enhance our senses. Now we have individuals with the ability previously deemed invasive (and perhaps just a side effect of correcting a birth defect or an injury). Perhaps sight down into the deep infrared. Or acute hearing, perhaps into the cell-phone RF band, or ability to hear heart rate at conversational distance (detect stress or deception).
What then? Will their freedom of action be curtailed?
My sense is Judge Posner gets it right. At the end of the day when everything about us is knowable by accident or on purpose, it’ll be the law, a court and a judge that protect us by deciding what is admissible. And we will return to a time of deeds being the only determinant, not words, thoughts or mime. Similar to the way we lived centuries ago, where no one had any real secrets, given small towns, extremely limited migration (died where you were born), and town gossips.
January 5, 2010, 9:30 amOren says:
Sure, but that’s all statutory.
Probably? There goes the magical simplicity of the rule in favor of some (as-yet unannounced) exceptions.
Not really. Whatever the military one gains in technological advances, the police one gains from being 30 feet from the target in a stationary vehicle.
If anything, the police have a far better image than the gunship crew.
January 5, 2010, 9:50 amjccamp says:
Oren –
I think maybe this discussion is getting derailed. No device which allows law enforcement to see within the walls of a private home will ever be allowed without a warrant. Period. There is an abundance of case law on the topic. For instance, “a home is a place in which a subjective expectation of privacy virtually always will be legitimate…”(quoted in California v Ciraolo but which includes multiple cites). The devices which are being discussed do not penetrate the walls, nor do they allow one to locate or “see” (identifiable) objects or persons. The sole function being considered is to locate temperature spikes uncommon to the structure type and location. All that fancy sci-fi AC130 stuff is clearly off-limits and outside this case.
What is being considered is whether, given the common availability of hand-held temperature gauges, do you still have an expectation of privacy regarding the temperature escaping to the outside from your house? That’s it. The rationale is that if any person can stand on public property or somewhere else lawfully, and using such a device, see the temperatures, then probably the police can too, for to deny to law enforcement what any adult or child, while doing completely legal behavior, can do, does not make sense.
As to my use of “probably”, I repeat, there is no One Size Fits All here. For instance, if you do something illegal in front of your picture window, for all the world to see, then that behavior can probably be observed by an officer and used for a search warrant affidavit. However, if the officer has to use a giant telescope to see the same thing, then it probably cannot be used because the cop is violating your expectation of privacy, by using his telescope. But I do not think that if your neighbor uses the same telescope and looks into your window, the neighbor commits a crime. You leave your curtains open at your own risk. So here is a conflict to my “good operating theory.” It wasn’t always so, but there is case law on point which controls.
BTW, if that same neighbor, using the same telescope, looks through your window and sees a crime occurring, and if he/she is willing to swear to that, then his/her statement can probably be used by law enforcement, as long as law enforcement did not solicit, encourage or otherwise influence the neighbor to do so. What’s wrong for the cops may not be wrong for the neighbor, if the neighbor acted independently and not as an agent of government. That may be what happens in the temperature scanner case. One standard for civilians, another for law enforcement.
January 5, 2010, 11:12 amjccamp says:
And also, if the cops have better equipment, it’s for tactical use, not investigative purposes. Big difference.
January 5, 2010, 11:13 amOren says:
Your certainty is disconcerting, to say the least. The decision was 5 to 4 and might even be already defunct if SS sides with the government. If a future administration appoints a few more Rehnquists to the Court, Kyllo is toast.
It’s perplexing that you would call a device that’s been in service since the late 1980s as “science fiction”. It is most certainly science-fact and the latest developments (for instance, on the Predator/Reaper drones) are probably even more impressive but, alas, still classified.
You seem to confuse the temperature gauge with the temperature imager. If you reread the top post, there are multiple commercial ones available, many in frequent use in HVAC applications. They produce images like this one.
A rationale that, whatever its merits, has very little in common with 4A jurisprudence as it exists.
Which entirely ruins your framework for analyzing these things.
And I’m sure when it’s not in tactical use it will be locked in a vault where no one can get to it.
January 5, 2010, 12:39 pmFred in IT says:
OK – Maybe I missed something here… but why didn’t the police just get the warrant that was needed in the first place? If there was probable cause I would imagine they could have found a judge willing to sign off on it.
To me, the flashlight argument is stupid as there is 5000+ years prior art to a flashlight… and the Brits still use it as the term for flashlight… that being ‘a torch’
There are two things that need to be kept in balance here… the Police (empowered by the people through The State) the ability to do their jobs in accordance with the will of the people. And the people the ability to live in freedom from oppression from the police.
That’s why we have the courts with Libra as their mascot.
But no matter how you slice it, dice it or whatever, the Police, Courts and Legislative bodies (The State, as a whole) all get their power from the people via the vote. We get the government we select.
January 5, 2010, 1:19 pmOren says:
They did not have PC before conducting the search, only the officer’s hunch that there was a grow operation. The IR search generated the PC that was used to apply for a warrant.
January 5, 2010, 1:26 pmMikeW says:
I have no professional legal experience but do have experience in thermal imaging technology (used the Agema 210). The thermal imagers are a world apart from cheap touchless IR temperature probes. Imagers can detect absolute temperature at far greater detail and accuracy than an IR probe.
Good IR probes (like the Raytek cited above) have a spot ratio of 12:1 meaning at 12′ away the temperature is an average reading over a 1′ diameter circle. The sensors are not temperatures corrected, most assume 74-76F ambient temps. If you read from a reflective surface like aluminum siding or white paint you can kiss any accuracy goodbye.
Using a cheap IR probe in detect growing operations would be irresponsible and completely ineffectual.
January 5, 2010, 1:49 pmEd Robinson says:
This from a non-lawyer…
The 4th amendment seems pretty clear – my privacy is assured in
my person, home, papers and effects…
The fact that the Supreme Court decided a “general public use”
would justify violating the amendment seems to be a bit of a
non-sequitor. It makes no sense to me.
Perhaps if wrecking balls come into “general public use” then
the police could just knock the roof off to see what’s going
on inside.
I fear that the Constitution is being shredded more each day.
January 5, 2010, 1:55 pmOren says:
You must be reading a different 4A, my copy doesn’t have the word “privacy” in it. It states that they are secure from searches and seizures — the entire case in Kyllo centers around the antecedent question: is IR imaging a “search” at all?
January 5, 2010, 3:36 pmChris Travers says:
This is what I am looking at though.
For example, the issue of reflecting a laser off a window and reconstructing conversations doesn’t seem to me conceptually different than shining a flashlight through the window and presumably police are allowed to do this. So if we try to base this on ownership of photons, I am not sure that gets us very far.
I think a better question is how invasive the technology actually is, and whether we, as a society, believe that social expectations of privacy are legitimate. In this regard shining a laser at a window to detect vibrations of that window is VASTLY different than shining a flashlight through the window. Similarly, just because one might in the future have a mm-radar system for, say, looking for wiring or plumbing in walls shouldn’t make the use of it to scan human bodies any less of a strip search.
January 5, 2010, 3:42 pmEd Robinson says:
Is there a reference to “privacy” anywhere in the document?
I don’t believe so but we all assume it is a basic premise.
“Secure” would seem to imply a “reasonable expectation” of privacy.
I’m afraid you sound like Mr. Clinton – how do you define sex?
January 5, 2010, 4:15 pmBuddy Hinton says:
my copy doesn’t have the word “exceptions” in it either.
January 5, 2010, 4:30 pmKirk Lazarus says:
Sometimes. So what? There’s this thing called encryption. Cell phone signals are encrypted between the handset and the base station already. Would you rather the government ban the possession of radios that receive certain frequencies?
January 5, 2010, 5:10 pmKirk Lazarus says:
Yes they are passive.
January 5, 2010, 5:11 pmKirk Lazarus says:
No matter what the courts say the government’s henchmen will use whatever technological means are available to them to spy on people they have an “interest” in. The information so obtained is very desirable and empowering to them even if it cannot be used as evidence in court. It is much better that these technologies be widely known and available, and protection against them routine, than to rely on the illusory protection of a piece of paper. You cannot live in a transparent house and expect privacy, whatever your constitution says.
January 5, 2010, 5:22 pmToby says:
In many parts of the country, utilities will subsidize customers to get home energy audits, which often include such scans. The cost of these subsidies are fully accpeted by the local PUC as a approved cost for inclusion in the rate base.
I assume you are a customer of Southern California Edison. I know SCE has funded man audits of commercial buildings including “re-commissioning” I do not know if SCE does the same for homes if it includes IR scanning.
January 5, 2010, 5:23 pmToby says:
Cursed be my typing…
…many audits of commercial…homes or if they include….
January 5, 2010, 5:30 pmKirk Lazarus says:
It’s unsustainable for thermal imaging equipment to be available to the public but not the police. Eg Citizen playing with his IR goggles notices his unshielded neighbor getting into some horizontal action in his 12 year old step daughter’s bedroom nightly. He reports this to the police and they say there’s nothing they can do about it. Doesn’t sound like that would last very long. It’s also unrealistic to expect the police to privately comply with such a prohibition.
January 5, 2010, 5:31 pmOren says:
Please speak for yourself. The notion of privacy is a 20th century one, it would entirely bizarre to believe that the 18th century founders intended to encode it into the Constitution.
The Constitution protects tangible liberties, persons, houses and such like from government intrusion, not intangible notions like privacy.
You have that entirely backwards. The thing that is secured is only something in which you have a REP. For instance, you have no REP in “open fields” and so open fields are not secure against warrantless searches.
So the question of whether your home is “secure” against an infared-imaging search cannot be resolved without figuring out whether you have a REP in the thermal radiation. The Court said yes because such technology was rare and hence the expectation of privacy was not unreasonable.
The exception is to the warrant requirement (which is judicially created), not the reasonability requirement (which is Constitutionally mandated). You are secure (in your home/person/effects but not open fields) from unreasonable S&S, not warrantless S&S.
They key question in any S&S is whether or not it was reasonable — and it is not crazy for the Court to say that entering a house without a warrant when in hot pursuit of a fleeing suspect is perfectly reasonable. In fact, it would be quite unreasonable to allow a fleeing suspect to escape arrest simply because he ran into a home.
January 5, 2010, 5:59 pmBuddy Hinton says:
um, no:
I see “warrants.” I don’t see “exceptions.”
January 5, 2010, 8:53 pmKirk says:
I will not doubt the veracity of your argument that perhaps a thermal imaging device could be considered in general use (or at least the single point thermometers). But it brings me to a point that I think chokes our legal system. And that is that lawyers have distorted reality in the court room.
I will grant you that point and read thermometers are generally available to the public. But they are not in general use. The thing I noticed is comparison to a flashlight. I am now 43 and am confident that even before I was born one could borrow a flashlight from most any neighbor willing to loan it out. I am confident that every one of my neighbors own one.
Now lets examine the thermometer. I am a geek. I socialize with geeks. My (untested) instinct is that surely one of my friends must have one of these. But I wouldn’t know for sure which and would plan on several calls. Further, I would be shocked if I could locate five people who owned one. As for the cameras, I would be rather surprised if any of my friends does have one. (I would certainly expect that it would be bragged about.)
If you asked a juror if flashlights are common only an unreasonable person would answer no. We need a return to common sense where such could be decided in a fair manner such as ask all the members of a jury pool about their use of an object. If an overwhelming majority use a device (as I am sure would be the case for a flashlight) then it is common. If not (as I am sure would be the case for a point and read thermometer), then it is not common.
January 5, 2010, 8:57 pmAri Tai says:
What is RC in these cases? What if one (two?, three?) neighbors call the police and state “I think Ari is growing pot in his attic, there’s never as much snow on his roof as ours, his friends have the smell of the weed around them and seem inebriated more often than not.” But it turns out they actually used a commodity camera with the IR (software) filter turned off to increase their certainty over 50% and guessed the rest (aka why some cameras (accidentally) image thru clothes better than others).
Does it change if it’s a “neighborhood watch” group?
When do the police lose rights that the citizen has to observe and report (and even act)? (given the police have no rights in excess of the citizen).
Which reminds me of the lack-of-clarity and limits placed on police, FBI, DoD, and intelligence agencies use of the internet in support of investigations and the electronic equivalent of “walking a beat.” What queries can they do when (under what identity), and store for later data mining for how long? What happens when Google maps are mined for IR data from street data images? And the internet way-back machine is minded for differential data (house was cold then, now it’s warm)? Etc. Will this divide between what a citizen and government can do continue to grow? My sense is it is already a factor of 10x better to be a concerned citizen than a government employee. Who enforces (besides the exponentially growing legal work force in all of these agencies doing these interpretations and just to be safe moving a step back from their interpreted line..)? What are the costs? Given our rule-set and sensibilities, maybe we should tell the citizenry to self-organize and pursue these issues because the government’s hands are tied. Oh my.
January 5, 2010, 11:24 pmOren says:
You see the word warrant but you fail to parse the sentence:
(1) The people shall be secure against unreasonable S&S.
(2) Warrants shall be issued only with probable cause and be particular.
The second clause was a direct response to the Writs of Assistance in which the British used these writs as general warrants to search any property at whim, thus evading the restriction (i.e. because they had “a warrant”). That is, the second clause limits the scope of warrants, not the scope of searches.
January 6, 2010, 1:17 amBuddy Hinton says:
Um, no. The second clause says that warrants govern searches and seizures and does not suggest that there are any searches and seizures not governed by warrants. If warrants are not required, then the prohibition on general warrants becomes meaningless because whatever authority would just authorize what a “Writ Of Assistance” authorized, but without resorting to a “Warrant.” The second clause becomes meaningless unless warrants generally ARE required for searches and seizures. And I don’t think I am out on a limb when I say this. I believe that this is mainstream ConLaw.
Please understand my main point in bringing this thing about “exceptions” up, Oren. I am NOT saying that there should no judicial exceptions to the warrant requirement that 4a directly imposes. I am merely countering your argument that “privacy” is irrelevant because the word does not appear in 4a. When sensibly parsing 4a, it is often downright necessary to go beyond the language of 4a itself. I am using the example of unwritten “exceptions” as an example, because I think it is one that you are predisposed to understand. Or at least I thought that. Now I just think you are being obstructionist by denying that the warrant requirement is (generally speaking) a requirement.
January 6, 2010, 7:10 amwuzzagrunt says:
My instinctive reaction is to view this as a search…but is it really? Heat is another form of radiation, so do the authorities need a warrant to drive around an area with sensors that detect nuclear radiation? Does the FCC need a warrant to triangulate the source of unlicensed radio broadcasts (set aside, for a moment, the question of whether licensing radio frequencies is valid). Those forms of radiation require specialized equipment not in “general public use” to detect.
The heat signature the thermal imaging equipment is detects is actually outside the structure. The radiation is no longer in your home, and it no longer belongs to you.
I’m not thrilled about it, but I’m not sure it’s a 4A violation.
January 6, 2010, 9:57 amMorty says:
Perhaps the term “general public use” is intended to mean more
January 6, 2010, 11:48 amspecifically “general public use outdoors and looking at other
people’s houses”. That is, the reason “general public use” removes the
expectation of privacy is because once this technology is widely used
outdoors, people who expect privacy will guard against it. So it
should not matter if the technology is cheap, widely available, and
even widely used by people to inspect the insulation in their own
homes, because people still don’t worry that someone is standing
outside their house and using thermal sensors to see through their
walls. Only in the scenario described above, where members of the
public are known to walk around with heat-sensing goggles, should the
“general public use” test be met.
John Moore says:
This isn’t true. The thermal imagers used for temperature audits (and medical purposes, and other things) are in some ways better than the AC130 stuff, but both are long-wave IR imagers.
My local police department has thermal imagers installed on some of their cars, so they can get the same sort of image as the AC130. Even the car used by Sheriff Joe’s reserve officer has one. All police helicopters in the area (and probably all police helicopters in the country) have FLIR, which is the same thing as on the AC130. I have monitored police transmissions where they used it to determine which cars parked on a street had been driven recently (by the heat from their hoods), and others where they spotted fleeing suspects hidden in brush by the leaking heat.
A new upcoming threat, in this regard, is the so-called “smart grid.” When it provides real-time telemetry of your electricity usage to a central point, it becomes a natural temptation for law enforcement to monitor that time series for signatures of suspicious activity (the ubiquitous marijuana grow lamp systems, for example).
January 6, 2010, 3:45 pmOwen H. says:
EVen if it is a grow room, that does not necessarily mean it is for illegal purposes. What if I am cultivating orchids? The evidence of growing lights and water use are not themselves indicative of a crime. You need other information to substantiate probable cause. As I said, it’s rather like saying my long hair is probable cause (which some cops do seem to think, btw).
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