UC Irvine

The legal system relies on voir dire to ensure the Sixth Amendment guarantee of an impartial jury. This dissertation tests the assumptions of voir dire that venire jurors 1.) can identify their biases accurately and 2.) will report them honestly. It was proposed that venire jurors would underreport their bias. As a result, we hypothesized that a significant proportion of venire jurors who claim that they are impartial would be inaccurate. The present study sought to disentangle whether the jurors are inaccurate because they are unaware of their bias or unwilling to admit it. First, it was hypothesized that increasing participant’s privacy during voir dire would increase their disclosures of bias. However, it was also hypothesized that increasing venire juror’s candidness would not increase the accuracy of their self-reports of bias. That is, we expected to find evidence that jurors underreport bias because they lack awareness of it.

The present study was conducted at the Orange County Superior Courthouse with 382 venire jurors. An anti-defendant bias was induced experimentally in a sample of the participants through exposure to pretrial publicity (PTP). The participants then completed a mock trial. During voir dire, participants were asked about their ability to be impartial. Participants exposed to PTP were randomly assigned to complete voir dire either through an in-person interview or a paper-and-pencil questionnaire. Then the participants read a case summary and rendered a verdict. Last, participants completed a post-verdict questionnaire assessing how they thought the PTP affected their verdict.

The data revealed that the majority of PTP-exposed venire jurors (70%) maintained that they were not biased. However, privacy did not influence their self-reports of bias, revealing no support for the hypothesis that venire jurors systematically underreport bias. Further, the findings did not support the hypothesis that venire jurors’ self-reports are inaccurate. Participants who said that they were biased were significantly more likely to convict (48%) compared to those who said that they were impartial (21%). Participant’s accuracy also did not vary as a function of their level of privacy during voir dire. Overall, these findings suggest that venire jurors can and do provide accurate self-reports of pretrial publicity bias.