Diverse Juries Perform Better Than All-White Juries
A fascinating study, authored by Samuel Sommers of Tufts University, examined decision making in diverse groups compared to non-diverse groups in a jury setting. He put together 29 mock juries of 6 people each; half of the juries consisted entirely of white people, and the other half of 4 white people and 2 African-Americans. Apart from the ethnicity, the jury selection was randomized. Each jury was then presented with a video of a trial with opening statements, witness testimony, forensic evidence, and closing arguments.
What was notable about the findings was how decision making differed between all-white and diverse groups. In deliberating, diverse groups discussed a greater breadth of information than non-diverse groups. Diverse groups also discussed more of the facts in each given case, and when evaluating the facts, were less likely to make factual errors. And when it came to looking at what information was missing from the presentations of the cases, diverse groups were more likely to examine this missing evidence.
Interestingly, the largest area of difference between these groups was that white jurors behaved differently – considered more facts and a wider view of the cases – when they were deliberating in a diverse group than when they were part of all white groups. It is encouraging that the exchange of information was greater in diverse groups. But what is even more fascinating is not just that the amount of information being passed around was greater, but that the bringing together of diversity created a “chemistry” of deeper thinking within the group. It would be fair to say that the group was smarter when it was diverse. And it is important to bear in mind that what these groups were talking about was detailed and complex. They weren’t guessing how many jelly beans were in a jar, they were weighing up a complex set of evidence, with missing pieces of information, to come to a challenging conclusion. In other words, they were dealing with situations that reflect the real world.
The study begins with a quotation from Thurgood Marshall that summarizes the effect of diversity in decision making groups extremely well:
“When any large and identifiable segment of the community is excluded from jury service, the effect is to remove from the jury room qualities of human nature and varieties of human experience, the range of which is unknown and perhaps unknowable. It is not necessary to assume that the excluded group will consistently vote as a class in order to conclude, as we do, that its exclusion deprives the jury of a perspective on human events that may have unsuspected importance in any case that may be presented.”