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The all-white jury v the diverse: Evidence, for a change


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This week we deliberate

The All-White Jury Vs. the Diverse:
Some New Evidence

Some juries work more carefully than others.
Does race play a role?



by David Dobbs
Editor, Mind Matters

In the long, messy experiment that is the trial by jury, one of the most volatile and closely attended variables in the United States is a jury's racial make-up. Depending on context, the phrases "all-white jury" or "all-black jury" can raise a host of expectations -- among them, as MIT social neuroscientist Rebecca Saxe notes below, the expectation that deliberations may be less than fair. The 1995 acquital of O.J. Simpson of murder charges by by a jury of nine blacks, one Hispanic, and one white, for instance, was widely seen as skewed by race, as was the 1992 acquital by a mostly white jury of the police officers who were videotaped beating Rodney King the year before. As Saxe explains below, the idea that diverse juries are more fair, however egalitarian in origin, enjoys little empirical support, because no one has done controlled studies comparing the verdicts and deliberations of both diverse and homogeneous juries on the same trial evidence. The study reviewed below, however ("On Racial Diversity and Group Decisions Making" -- pdf download ) that did exactly that, creating a number of mock juries, some all-white and some of mixed racial make-up, to deliberate evidence from a racially charged sexual assault trial. The results illuminate not just whether but how racial diversity affects jury deliberations and discussions about race.


How to Fill a Jury Box:
Race Matters

by Rebecca Saxe Brain and Cognitive Sciences Departmemt
Massachusetts Institute of Technology
Cambridge, Mass.

Rebecca Saxe

"The jury, which is the most energetic means of making the people rule, is alsothe most efficacious means of teaching it to rule well."

- Alexis de Tocqueville, Democracy in America (1835)

Many liberals share the vague intuition that a racially diverse (or representative) jury is "better" than a racially homogenous one. The arguments for this view tend to be murky, though. Who benefits, and how, from racial diversity in the jury box? In a recent paper in the Journal of Personality and Social Psychology [pdf download ], Tufts University psychology professor Samuel Sommers argues that this is an empirical question, and he provides a surprisingly powerful answer: when making a complex, ambiguous decision, everyone in a diverse group benefits.

Why Diversity?

A priori, two basic arguments can be made in favor of racially representative juries. The first argument concerns the appearances and procedures of the jury trial. For instance, racially mixed juries may increase the legal system's perceived legitimacy even if they do not influence the actual outcome of the trial. They may also satisfy constitutional questions about the nature of the "right" conferred by the sixth amendment: What kind of representation is guaranteed by an "impartial jury of the State and district"? Finally, jury duty can be considered an honor or social opportunity; if so, equal representation on juries would be a civil right of the prospective jurors themselves. Critically, all of these arguments apply even if diversity has no real impact on juries' performance.

The second, bolder argument for racially mixed juries is that diversity actually influences jury decision-making -- for the better, advocates say. Popular opinion seems to endorse this claim, as when the public blames a jury's racial composition for unpopular or seemingly unlikely verdicts. There was popular uproar in 1992, for example, when the white police who had attacked Rodney King the year before were acquited by a jury of 10 whites and no blacks. The empirical evidence for this stronger claim about fairness, however, is slim. The first questions Sommers addresses is therefore: Does racial diversity of a jury lead to materially improved deliberations? His answer is, in a word, yes.

Mock Juries Weigh Real Evidence

In the study, Sommers asked 30 different mock juries, each composed of six adults, to watch a video summary, edited from Court TV coverage, of the trial proceedings of an actual sexual assault case in which a black male defendant allegedly assaulted, separately, two white females. Sommers went to extraordinary lengths to make these mock trials as much like a real trial as possible. The study was conducted in a courthouse. Participants were jury-eligible adults who were at the court for real jury duty. Their age ranged from 18 to 78. Only racial composition was varied systematically: half of the juries were white, and the other half were made up of four white and two black jurors.

The facts of the case were disputed and required jury deliberation. For example, one of the victims described a scar that matched a scar on the defendant's torso, but neither victim recognized his face; semen and hair left on the victim provided evidence that was consistent with the defendant's but not a definitive match. In the end, the majority (55 percent) of the mock juries voted unanimously to acquit, just as the real jury had. But both verdicts and deliberation quality and content varied significantly depending on the juries' racial make-up.

Calling the Race Card

Mixed and all-white juries were equally likely to raise the subject of race when discussing the case -- but differed sharply in how they reacted to the subject once it was raised. Every time racism was mentioned in an all-white jury, at least one juror objected that racism was not relevant (J5: "What about the fact that he was a Black man?" J6: "What does that have to do with it?"). That's a 100 percent rate of objection to the idea that race was relevant. In the diverse juries, by contrast, only 22 percent of mentions of possible racism met with objections. Meanwhile, the diverse juries deliberated longer, cited more case-relevant facts during deliberation, made fewer factual mistakes, and were more likely to correct inaccurate statements than the all-white juries were. So who among the jurors is creating the difference in dynamics between the homogenous and heterogeneous juries? One possibility is that the black jurors alone improved jury performance. Black jurors may have different life experiences that lead them to contribute unique information and perspectives to the deliberations. By this hypothesis, it is the sole burden of the black jurors to provide the benefits of diversity. But Sommers' data tell a very different story: He found that white jurors were actually responsible for a large proportion of the group differences, as they behaved differently in a racially mixed jury than in one all-white. White jurors in diverse groups mentioned more facts, made fewer factual errors, corrected more mistakes and raised the possibility of racism more often than did white jurors in homogeneous groups. Even before the deliberations began, white participants who expected to deliberate with black jurors privately espoused less harsh views of the (black) defendant than did white participants who expected to deliberate in an all-white group. Both the anticipation and the experience of serving on a diverse jury seemed to sharpen the white jurors' sensitivity not just to race but to accuracy and due process. One explanation for this pattern is that white jurors felt more motivation to avoid prejudice in the presence of black jurors. The motivation to avoid prejudice could lead not only to more careful consideration of racism itself, but also to more systematic and thorough information processing of all relevant facts about the defendant.

A Win-Win for Juries and Justice In all, Sommers' data show that diverse juries reason better, not just as groups but as individuals; everyone on the jury benefits, and justice, it appears, is better served. As Sommers concludes, these results make the benefits of diverse juries not just more concrete but readily attained. Minority jurors need feel no burden or need to "educate" white jurors or convey a unique minority perspective; diversity seems to do its own work. The results suggest that representative juries do not merely honor a civil right or a constitutional ideal but provide an effective tool for achieving more thorough and competent jury deliberations.

Rebecca Saxe studies how we think about other people -- and how our brains construct these thoughts -- in the Brain and Cognitive Sciences department at the Massachusetts of Technology.

The views expressed are those of the author and are not necessarily those of Scientific American.

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