The Justice Department has justified the NSA domestic surveillance program under the Fourth Amendent by invoking the "special needs" exception to the warrant requirement. But does that rationale make sense? I thought I would take a closer look.

  First, some background. The special needs exception applies when the government is acting in a capacity beyond law enforcement. For example, imagine a high school principal needs to search a student's locker, or a housing inspector needs to inspect a house, or a government employer needs to search an employee's office for evidence of workplace misconduct. In these cases, it would frustrate the legitimate government need beyond law enforcement to require a traditional criminal law warrant. The "special needs" cases recognize that the government may wear lots of different hats, and imposes a more general reasonablness balancing rather than a traditional warrant requirement when the government is pursuing that non-law-enforcement interest.

  Here is how Justice O'Connor summarized the basic doctrine in O'Connor v. Ortega:

"[I]t is settled . . . that `except in certain carefully defined classes of cases, a search of private property without proper consent is "unreasonable" unless it has been authorized by a valid search warrant.'" Mancusi v. DeForte, 392 U.S., at 370 (quoting Camara v. Municipal Court, supra, at 528-529). There are some circumstances, however, in which we have recognized that a warrant requirement is unsuitable. In particular, a warrant requirement is not appropriate when "the burden of obtaining a warrant is likely to frustrate the governmental purpose behind the search." Camara v. Municipal Court, supra, at 533. Or, as JUSTICE BLACKMUN stated in T. L. O., "[o]nly in those exceptional circumstances in which special needs, beyond the normal need for law enforcement, make the warrant and probable-cause requirement impracticable." 469 U.S., at 351 (concurring in judgment).

DOJ's argument is that the exception applies because intelligence collection is a "special need, beyond the normal need for law enforcement" (emphasis added). And of course, that's right in a formal sense: Intelligence collection is different from law enforcement. So in that sense, there is a "special need," and the application of the doctrine makes sense.

  However, there is an important potential wrinkle in this argument that I don't think anyone has noticed yet. The fact that the exception applies in some way does not indicate exactly how it applies. And there is a plausible case to be made that foreign intelligence is a special need, but that FISA warrants are still required to conduct foreign intelligence surveillance

  The key, as I see it, is that FISA warrants are themselves "special needs" warrants. The Keith case that inspired the passage of FISA considered the application of the "special needs" doctrine to domestic intelligence monitoring, and held that the existence of "special needs" justified the replacement of the traditional criminal law warrant with a special intelligence warrant — but, notably, not the elimination of the warrant requirement itself. As a result, it doesn't make sense to apply the "special needs" exception to say that the "special needs" warrants required under FISA are no longer required. Whether a need is "special" is relative to the type of warrant, the thinking would run: In the contect of FISA's warrant scheme, intelligence needs are not "special." So while foreign intelligence collection is a special need relative to the Fourth Amendment requiring criminal law warrants, it is not a special need relative to requiring FISA warrants.

  That's the argument, at least. Is it persuasive? What do you think? There are a few counterarguments to be made. For example, you could say that foreign intelligence is different from domestic intelligence. That is, you could say that the special needs doctrine relaxes the warrant requirement from a criminal warrant to a FISA-like warrant in the case of domestic surveillance (see Keith), but that foreign intelligence needs further relax the warrant requirement from a FISA-like warrant requirement to no warrant requirement. In other words, FISA warrants may be special needs warrants, but they are special needs warrants needed for domestic intelligence collection but not foreign intelligence collection. This is a possible argument, but as far as I know no court has directly addressed it: United States v. Truong Dinh Hung, 629 F.2d 908 (4th Cir. 1980), was perhaps the closest, but it was based largely on notions of institutional expertise — and footnote 3 of the opinion ackowledged that the then-recently enacted FISA statute could very well alter the institutional expertise balance.

  Second, you could also say that it would be just too strange if the "specialness" of the need varied based on the type of warrants that Congress happen to authorize at any particular time. Congress can authorize all type of warrants, and it may seem intuitively odd that whether the Fourth Amendment requires a warrant hinges on whether Congress has created a statute authorizing that kind of warrant to be granted. For example, imagine Congress created a statute authorizing "home inspection" warrants, which could be issued based on probable cause to believe that a home needs a safety inspection. Would the existence of the new statute mean that housing inspections are no longer a "special need," because the needs are addressed in the new statute? Would the new statute alter the constitutional rule, requiring a warrant (albeit a home inspection warrant) where before no warrant was required? The interaction between constitutional warrant requirements and preexisting statutory warrant authority comes up from time to time in the cases, and hasn't been definitively resolved.

  By way of background, it may be helpful to note that, at least as I understand existing law, I don't think the seriousness of the Al Qaeda threat has a direct bearing on whether intelligence surveillance counts as a "special need" under the Fourth Amendment. My sense of the cases is that they ordinarily look to the general interest abstractly (such as a housing inspector's interest in safe houses) rather than the specific interest in the specific context of that particular search. Further, please understand that the "special needs" exception doesn't end the inquiry: other exceptions may apply even if special needs doesn't permit a warrantless search. Still, DOJ is relying on the special needs exception, so I think it's worth thinking critically about how the exception applies in these circumstances.

  UPDATE: I added a new paragraph shortly after posting the original.