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Group Diversity: Mock Juries Reveal Surprising Effects of Diversity on Groups

Samuel R. Sommers (Credit: Melody Kol, Tufts University)

When it comes to group decision-making processes, diversity is generally viewed as a good thing, a broader range of perspectives leading to a wider range of information and a more balanced outcome. In terms of racial or ethnic diversity, says Samuel R. Sommers, an assistant professor of psychology at Tufts University, “at some level, it assumes that there exists some monolithic black perspective that they are going to infuse into the discussion. And that is probably unfair and unrealistic,” he says.

Nevertheless, racial diversity does tend to improve the performance of decision-making groups. That's the conclusion of a recent study conducted by Sommers and published in the April issue of the Journal of Personality and Social Psychology. "On Racial Diversity and Group Decision Making: Identifying Multiple Effects of Racial Composition on Jury Deliberations" shows that in a mock jury, placing white jurors in diverse groups raised their performance level, encouraging them to cite more facts, make fewer mistakes, deliberate longer, and conduct broader and more accurate discussions--compared to peers in all-white mock juries. Racially mixed juries were also much more willing to discuss issues of racism.

Sommers spoke with MiSciNet contributing writer Anne Sasso about his study and its implications for other groups facing controversial issues.

MiSciNet: Your study observed the behavior of mock jurors in all-white and racially mixed juries as they deliberated a case involving a black defendant. The results were interesting and somewhat unexpected. What did you discover?

SAMUEL R. SOMMERS: Traditional assumptions about how diversity influences decision-making focus on the idea that having nonwhite individuals in a group will lead to different perspectives being raised in the group. But one of the interesting and somewhat counterintuitive findings that the study produced is that white participants behave very differently when they’re in diverse settings versus in all-white settings. [In diverse settings] they raise more facts regarding the trial. They make fewer factual inaccuracies in their statements about the case.

MiSciNet: Does group diversity act as a performance enhancer?

S.R.S.: At the group level, that seems to be a reasonable conclusion. I think people would agree that you want juries to raise a wide range of perspectives and information. You want them to be true to the facts of the case and accurate in their fact-finding. You want them to be open-minded. And on all those counts, diverse groups seem to be doing better than all-white groups.

When society talks about diversity, much of the conversation focuses on ideology and the morality and constitutionality of how to achieve diversity. I think that looking at the observable effects of diversity on a group’s performance is a really fruitful way to get a sense of what diversity really means.

MiSciNet: Diversity appears to raise the awareness levels and attention to detail of white jurors; does it have a similar effect on black jurors?

S.R.S.: Would a diverse group perform better than an all-black group? You could probably predict that yes, it would. But we don’t know that from this study. We didn’t study all-black groups, but it’s a very important question. Being in a diverse setting has a motivational influence on the white jurors; it gets them scrutinizing information more carefully knowing that they’re going to have to discuss it with a diverse group.

MiSciNet: In your study, some of the changes in the behavior of white jurors took place before there was any interaction between the jurors. Was it simply a question of seeing the make-up of the group?

S.R.S.: Absolutely. Before they even open their mouths or have any form of interaction at all, the racial composition of the group seems to be exerting an influence on the white jurors.

MiSciNet: So, do you think that we operate under different default settings depending upon who’s in our group?

S.R.S.: I do think you could make a case, and again we need to do further studies to test this, that in the all-white setting--maybe the default setting for the white participants--they’re a little bit more relaxed or content to rely on cognitive shortcuts. They don’t engage the information at quite the same level that they feel they need to when they’re in a diverse group. So, I think that’s a really provocative idea that somehow, at least when discussing a race-related issue, just knowing who you’re going to be interacting with can very well lead you to change the information-processing strategy that you use.

MiSciNet: Is this change in processing strategy related specifically to topics of race, or does it also apply to, say, discussions of particle physics?

S.R.S.: I think that a group’s composition has the potential to influence decision-making and group processes regardless of topic, but the specific nature of that influence probably varies depending on what they’re discussing. We’re finding in a follow-up study, for example, that these effects are strongest and more reliable when the group is discussing or thinks it’s going to be discussing an issue with some relevance to race.

MiSciNet: So, for example, is it reasonable to assume, based on the results of your study, that a diverse group reviewing grant proposals, or making hiring decisions, or reviewing a manuscript for possible publication, will usually make better decisions than a less diverse group?

S.R.S.: "Better" is always a tough issue from a decision-making perspective, as many decisions have no gold standard or "correct" response. But in this study, diverse groups consider a wider range of information, are more accurate, and are open-minded. These are, of course, good qualities for any group making a decision. So by those standards, yes, these data suggest that diversity often leads to better decision-making.

MiSciNet: Is it reasonable to conclude that a more diverse scientific workforce might do better science?

S.R.S.: Potentially, sure. Again, you want groups to be thorough, accurate, [and] willing to consider multiple perspectives, and in my study, diversity leads to these outcomes. Generalizations are dicey, of course, but on every objective standard in the study, diverse groups perform better than homogeneous ones.

MiSciNet: You also observed a greater willingness of whites to discuss race in the diverse groups than in the all-white groups. Why?

S.R.S.: When race comes up in an all-white group, there was always this palpable response of surprise mixed with irritation, as if they didn’t expect it to come up, and they didn’t really want to talk about it. I think for the most part whites would prefer to avoid talking about race. But being in these diverse groups is having an effect on them, whether it’s that they are less surprised when race comes up or that they have given more thought to issues related to race just by seeing who they’d be talking with. For whatever reason, they’re more amenable to this discussion.

MiSciNet: It seems as if being in a diverse group acts as a reminder to avoid prejudice.

S.R.S.: Yes, it certainly seems to get whites to think about those things. We know from other research in social psychology that in interracial interactions, whites have different thoughts, concerns, and motivations than they do when they’re in an all-white setting. And I think it’s plausible to suggest that those thoughts are having some effect on the way they process information and behave in this setting. Simply by virtue of membership in a diverse group, they are engaging in this more systematic processing.

MiSciNet: How does this research extend beyond jury composition?

S.R.S.: This should be relevant in any context in which you have groups of people making decisions and have issues of diversity at the forefront of the organization’s mind. Whether you’re talking about the classroom, the boardroom and the workplace, or decision-making committees in a variety of different fields, there are potential implications. Again, the study was run in a legal setting, but I think the issues that it raises are important for all group types. The fact that whites behave very differently in an all-white versus a diverse setting, and at least in this study, seem to be performing better in the diverse setting, has some profound implications and potential usefulness.

But I don’t think there’s a simple conclusion here of diversity always leading groups to do better. There’s research that suggests that there are potential downsides to diversity, many of them relating to morale and group cohesion. Sometimes those are overcome with time, but sometimes they’re hard to overcome. So, it’s a much more nuanced issue, but I do think that studying it from a performance perspective is a really useful way to go.

We often talk about the pros and cons of diversity in groups. I think this study, in a provocative manner, suggests the potential downside of homogeneous settings. At some level, homogeneity may allow people to become lazy when it comes to processing information and somewhat less accurate when it comes to recalling facts about a decision. It’s really interesting to think that the homogeneous status quo in many situations may be what’s problematic, not so much the efforts to change that status quo.

So I think that the finding that diversity is influential is not surprising. But it’s influential in large part because of the effects it has on whites. That is surprising. I think that’s important, because at some level it maybe makes the achievement of diversity more attainable, more palatable, and more consistent with the desire to improve the performance of everyone in a group.

This material is based upon work supported by the National Science Foundation Grant No. SES-0549096. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

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