Cognitive Depletion and Motivation to Avoid Prejudice during Jury Deliberation

Racial diversity in juries ensures representation of minority voices and can reduce racial bias in verdicts. But can diversity also jeopardize verdict fairness by placing a strain on individual jurors’ self-regulation and cognitive resources, and in turn, weakening the performance of the group? I tested a contextual model of cognitive depletion during jury deliberation in racially homogeneous and racially diverse juries, aiming to reconcile the contradiction that diverse juries seem to perform better than homogeneous ones (Sommers, 2006), although there are detrimental effects of interracial interactions on cognitive processes (Richeson & Trawalter, 2005). In a mock jury deliberation paradigm, White jurors viewed an evidence presentation from the criminal trial of a man accused of murdering his wife, including a manipulation of defendant race (White, African American). Then they deliberated with three other White participants and either 2 White or 2 African American confederates (resulting in all-White or diverse juries) and completed several measures including verdicts, cognitive depletion (i.e., the Stroop task), memory for case facts (a measure of performance), motivation to reach a fair verdict, individual difference moderators (i.e., action/state orientation and motivation to avoid prejudice), and control measures (i.e., racial prejudice, demographics). For other measures of performance, transcripts were coded to quantify the number of total, correct, and new case facts brought up by each juror during deliberation. Results indicated that, as predicted, jurors in diverse versus all-White juries were more depleted after deliberation. Yet their performance (i.e., ability to recall and discuss case facts) did not suffer as a result, regardless of defendant race. Further justifying the importance of racially diverse juries, jurors on all-White juries performed better when they judged a White (versus Black) defendant, yet racially diverse juries performed just as well when the defendant was Black. Results also indicated that jurors were overall more lenient toward a Black (versus White defendant) before and after deliberation. Regarding juror individual differences, action- versus state-oriented jurors performed better in some experimental conditions, but worse in others; action orientation was not related to depletion. Motivation to control prejudice did not moderate the effects of experimental manipulations.