Many thanks to Eugene for inviting me to make some comments on some recent research.

A few years ago I noticed in the Sourcebook of Criminal Justice Statistics that federal defendants who stand trial are much more likely to be acquitted in a bench trial than by a jury. This seemed odd to me -- I had always assumed the opposite was true. So I studied government records for federal trials between 1989 and 2002 and found a number of surprising things.

First, I found that the gap between bench acquittal rates and jury acquittal rates was quite large: over the 14 years I studied, the average conviction rate in jury cases was 84%, while judges convicted slightly more than 50% of the time. Second (using other data), I found that this gap was a recent phenomenon. Between the early 1960s and late 1980s, the conviction rates for judge and jury was roughly the same; the 20 years before that, judges actually convicted much more often than juries.

So the goal was to try to explain why this "acquittal gap" between bench and jury exists, and secondarily, why it had grown so large since the late 1980s. To make sure I wasn't stumbling around in an academic fog, I started by interviewing two dozen federal prosecutors and defense counsel to see if their instincts were the same as mine. They were: of the 24 lawyers I spoke to, only a very few knew or guessed that judges are more likely to acquit. The rest were mildly to strongly certain that juries were more favorable to the accused.

During the coming week discuss some of the variables I looked at -- type of case, seriousness of charge, type of defense lawyer, strength of the evidence, etc.), as well as some of the conclusions I drew. Questions, comments, and criticisms are welcome, aleipold@law.uiuc.edu. The full paper can be found at 83 Wash.U.L.Q. 151, from SSRN at http://papers.ssrn.com/sol3/papers.cfm?abstract_id=843606.

Wow. Some very thoughtful and perceptive comments were posted yesterday on the basic question of why federal judges are more likely to acquit than federal juries. This is fun.

Let me pick up on a few of the points that people raised in their posts, to show what the data revealed. These figures are based on a study of about 77,000 federal criminal trials completed between 1989 and 2002. Those who read yesterday's post will recall that I am trying to figure out both why judges are more likely to acquit than juries, and why the judicial conviction rate dropped sharply between the late 1980s and the early 2000s.

Several folks hypothesized that the type of crime involved -- violent, property, drug, etc. -- might explain the disparity. Perhaps certain types of crimes are both steered toward a particular factfinder and are particularly likely to end with an acquittal. For example (I speculated), financial and regulatory crimes might be directed toward judges because both sides worry that jurors will misunderstand the evidence, and perhaps it is also the complexity of these cases that make them hard for the government to win. Or perhaps defense counsel avoid juries in violent crime cases, and so on.

There may be something to this, but the figures don't show much of an effect by case type. I looked at six crime categories: violent, property, drug, immigration, regulatory (crimes involving customs, social security, the mail, etc.) and public order offenses (a group that includes primarily traffic offenses -- really -- and guns). Two things became clear: (1) juries always convict more than judges, no matter what category of crime, usually by 15 to 30 percentage points, and (2) defense counsel prefer juries to judges in all types of cases. In only one category did the percentage of bench trials come close to half: 45% of public order trials are tried by the court. Interestingly, judges convict in only 47% of the public order cases, compared to an 83% conviction rate by juries.

Another line of posts offered the insight that the "conviction gap" might be explained by the strength of the evidence. To paraphrase Judge Posner, perhaps innocent defendants want judges because they worry about a mistake being made, while guilty defendants want a jury trial, hoping a mistake will be made. I think this explanation has great intuitive appeal.

But two brief points on this. First, it is darn hard to measure the strength of the evidence, at least on a large scale. The best indicator we have of the case strength is the outcome, but that leaves us chasing our tail if we are trying to evaluate the outcomes. This doesn't make this explanation wrong, it is just hard to know if it is right.

Second, if strength of the evidence explains a big piece of the conviction gap, we still need an explanation for why the jury conviction rate has remained steady while the bench rate fell significantly over the period studied. So while I like this explanation very much, I worry it is still speculative and incomplete.

I have left out a lot of detail, much of which I hope is provided in the article (on SSRN, at http://papers.ssrn.com/sol3/papers.cfm?abstract_id=843606 and perhaps in other posts later this week As always, questions and comments welcome at aleipold@law.uiuc.edu.

Those who have been kind enough to follow the posts over the last two days have seen some terrific comments and questions about why federal judges are statistically more likely to acquit in criminal cases than juries are. Here are a few more findings, and then a couple of observations on the comments (The full study is available on SSRN at http://papers.ssrn.com/sol3/papers.cfm?abstract_id=843606.)

I mentioned yesterday that the category of crime the defendant was accused of committing (drug, immigration, violent, public order, etc.) showed some variation, but at the end of the road, judges always acquit more than juries, regardless of the crime type. That statement holds true across the following variables:

[1] Judges are more likely to acquit whether the crime is a felony or a misdemeanor. This was significant, since 89% of all serious misdemeanors (i.e., those for which defendant *could* have a jury) are tried to the judge, and 74% of bench trials involved misdemeanors.

I do think the high percentage of "bench" misdemeanors explains something, even if it does not explain the change in judicial behavior over time. My guess is that misdemeanor cases get less experienced investigators and prosecutors, less grand jury investigation, and less preparation generally. These shortcomings may not be obvious to a jury, but may be quite obvious to a judge, and thus may explain part of the conviction gap. But the gap remains when we look at felonies only, so this is a partial answer at best.

[2] Judges are more likely to acquit than juries regardless of the type of defense counsel -- private, panel, public defender, or pro se. I had wondered whether group norms or workload pressures might explain some of the differences, but they really don't. Defendants represented by different counsel type do roughly the same (badly) before juries, all being convicted at a 82% - 87% rate, while defendants with all types of defense counsel do much better in front of judges.

[3] Judges are more likely to acquit in all parts of the country. I wondered if differences in case loads, case mix, local rules, circuit law, and jury pools might lead to regional differences. Wrong again. In *every* circuit, the district court juries convict 80% to 89% of the time (the First Circuit has the lowest rate, the Seventh Circuit the highest), and in every circuit, the district court judges convict a lower percentage of the time, with most in the 50 to 70 percent range.

In fact, when I looked at individual districts, it turns out that juries convicted more often in 89 out of the 94 districts in the country. The five districts with slightly higher judicial conviction rates were the D. Colorado, W.D. Arkansas, E.D. Wisconsin, W.D. Wisconsin, and E.D. Missouri.

Tomorrow I'll talk about the conclusions I drew from these numbers. But here I'll briefly comment on a couple of the comments in the posts and some of the off-list emails.

1. Some folks asked if the political party, background, or age of the judge, or the identity of the appointing president was considered. It was not. The database I used did not provide this information, and it would have been a logistical nightmare to get it. A lame excuse perhaps, but I have doubts about the value of the information even if I could get it. I'm just not clever enough to put many of these variables to work -- when a district judge is appointed, how much of the decision is the President and how much is the State's Senators? Is a Massachusetts Republican the same as a Utah Democrat? I'm dubious that the results would shed enough light on the topic to make it worth the effort, although I know many people who would disagree.

2. A couple of comments raised the issue of sample election bias, a point I note briefly in the paper although not by that name. As I indicated earlier, this may be exactly right, but I don't know how to tell if it is right. Perhaps it is a pure strength-of-the-evidence calculation by the defense (strong case judge, weak case jury), but putting aside the difficulty of measuring this, I still wonder. This kind of analysis was sometimes but not routinely mentioned by the defense counsel I interviewed. The flavor of their comments was that juries were presumptively better in all types of cases, regardless of the evidence strength. (And BTW, many of the defense counsel very extremely candid with me about their strategies.) But if I do a follow up on this article someday, I agree that more statistical modeling could offer real insights.

Thanks to all for your continued interest. Comments welcome, aleipold@law.uiuc.edu.

Yesterday there were more very helpful posts and emails in response to the puzzle of why federal judges are much more likely to acquit than juries, and why the gap grew between 1989 and 2002. Today I will offer some tentative conclusions on what the data reveal, and respond to a couple of comments.

I mentioned earlier that the conviction gap between judge and jury was large, growing, and could not be explained by those variables I studied. Judges are more acquittal-prone in felony cases, misdemeanors, across all categories of crime, in virtually every judicial district, and with all types of defense lawyers. This led me to consider two other possibilities -- that juries are becoming increasing prone to convict regardless of the evidence, and/or that judges are seeing something in the cases that makes them increasingly likely to acquit.

[A] As to juries. Maybe the fear of crime and a law-and-order attitude are increasingly seeping into the jury box, making jurors willing to convict on lower and lower degrees of proof. Jurors know from watching Law & Order (and its 17 spin-offs, most of which are pretty good) that prosecutors are really good people who only really go after the guilty, and perhaps this mind set is making jurors more trusting of government evidence, which in turn encourages prosecutors to bring weaker cases to trial.

The problem with this theory is I couldn't find any supporting evidence. If prosecutors really were getting the same conviction rate on weaker evidence, we would expect to see some impact on the dismissal and reversal rates, even though these are admittedly very rough proxies. But the percentage of federal defendants who had their cases dismissed at some point in the process decreased over the period studied, and the reversal rate (for reasons other than faulty sentences) remained constant, with the exception of a small blip in 1996-97. People's fear of crime -- something that might lead to a more pro-prosecution attitude among jurors -- was variable, and did not track the conviction rates, which for juries was steady as a rock. And so while I can't say that juries are *not* prone to "over-convicting," I don't see, and have not read, any evidence that they are.

[B] Judges. The core problem is to find something about criminal trials that has changed since the late 1980s, something that would affect judges but not juries. With a tip of the hat to the many people who suggested this in their posts, I think the Sentencing Guidelines best fits this description. The Guidelines took away a huge amount of sentencing discretion, which meant that judges were more often faced with cases where they knew that a conviction would result in a harsh -- maybe too-harsh -- sentence. We don't have to say that judges were acting "lawlessly" to reach the unremarkable conclusion that judges may hold the government even more tightly to its burden of proof when the stakes are high and unforgiving.

Evidence of this is obviously hard to come by, and does not uniformly support the thesis. But consider: (1) the timing is nearly perfect, with the Guidelines really hitting stride just as the judicial conviction rate started to slide; (2) many, many judges were harshly critical of the how the Guidelines made it harder for them to do justice in individual cases; (3) there is social science literature to support the view that the greater the punishment the slower people are to impose it, but who needs social science? This phenomenon occurs in the law all the time. Few people doubt that the exclusionary rule's application is influenced by the seriousness of the crime and the importance of the evidence. The Supreme Court has recognized that concerns about the death penalty can influence jurors at the guilt stage. Frank Bowman and Michael Heise, in their terrific studies on drug sentences, suggest that harsh sentences influence prosecutorial and judicial decisions that are formally unrelated to punishment. It would hardly be surprising to learn that judges might require more and better proof of guilt when they cannot control the sentence. This would help explain why judges, but not juries, have changed their behavior since the late 1980s.

What conclusion to draw from this? The glib answer is that I need to do a follow up study in a few years, after the Booker dust has settled. The more serious answer may be that we think carefully about how we should strike the balance between consistent treatment of defendants and individual justice.

[C] Comments. Jim Lindgren and others raised a point that is really elemental. (I'll paraphrase) If judges are so stinkin' great for defendants, how come they all pick jury trials? More specifically, since Rule 23 says prosecutors or the court can veto a defense request for a bench trial, could it be that prosecutors know that they will do better in front of juries, and therefore routinely frustrate the defense efforts to choose the better factfinder?

Actually that was my first thought when I saw the statistics. But after interviewing lots of lawyers and reading lots of "how-to" trial manuals, I became convinced that prosecutors are not influencing the defense choice of factfinder in any meaningful way. None of the defense lawyers I talked to said that prosecutors frustrated their choices -- they put their clients in front of the jury because they want to. All of the prosecutors said they were rarely asked to agree to a bench trial, and when asked, they almost always agreed (unless the judge is "crazy"). The reasons are precisely those identified by Public_Defender in his or her post yesterday: prosecutors don't want to offend the judge. Also, none of the manuals I saw even hinted that bench trials might be a better choice, except in narrow groups of cases (child porn is the example that many use).

This still doesn't answer the question why defendants flock to jury trials. Are they just unaware of the conviction rates? (maybe) Do institutional inertia and agency problems make it easier for defendants to choose a jury trial? (Probably; if you go against the norm and lose, it's hard to explain to boss and client what you were thinking.) Is it really the case that factually guilty defendant overwhelmingly choose juries, because even if they don't have a great chance, it's better than before a judge? (The selection bias issue discussed earlier -- probably true.)

As always, I welcome thoughts on these or other issues, aleipold@law.uiuc.edu. The full paper can be accessed at http://papers.ssrn.com/sol3/papers.cfm?abstract_id=843606.

Thanks to everyone who slogged through the last four days of posts about judicial acquittals. The comments were extremely helpful to my ongoing thinking about the topic; I appreciate that so many took time to offer their insights. Thanks also to Eugene for inviting me. Hope to do it again sometime. Best, Andy