How Immigration Status, Ethnicity of Defendant, and Mock Jurors' Cognitive Processing Relate to Capital Jurors' Sentencing Verdicts and Endorsements and Weighing of Aggravators and Mitigators

During deliberations, capital jurors are expected to properly weigh aggravators and mitigators (i.e., factors that make the defendant more or less worthy of the death penalty) to arrive at an appropriate sentencing verdict. They are instructed to exclude extralegal factors irrelevant to the case. Bias might impede this ideal if verdicts and weighing are influenced by juror characteristics (e.g., cognitive processing traits) or irrelevant defendant characteristics (e.g., ethnicity and immigration status). In the current 3 x 2 between-subjects experiment, death qualified mock capital jurors read a trial summary based on a real case, endorsed aggravating and mitigating circumstances, reported how they weighed mitigators relative to aggravators, rendered a verdict, and completed measures of cognitive processing. The defendant in the trial summary was a U.S. born Caucasian American, a documented Mexican immigrant, or an undocumented Mexican immigrant. The number of aggravators and mitigators were also manipulated: Participants read a case with either 4 aggravators and 2 mitigators, or 2 aggravators and 4 mitigators. Results suggest documented Latino immigrants fall within the "normative window" of prejudice (i.e., the normative acceptability of prejudice expression towards them is ambiguous). With some caveats, participants with less experiential processing traits tended to display bias toward the documented Mexican immigrant, whereas participants with more experiential processing traits tended to display a bias toward the undocumented Mexican immigrant. In addition, participants with more rational processing traits were better able to weigh aggravators and mitigators. Overall, experimental manipulations, individual differences in information processing, and the interaction between them most strongly accounted for variation in aggravator endorsement, and most weakly for variation in sentencing verdicts. Legal implications, particularly for attorneys, are noted and discussed.