The Importance of Trial Ambiguity: Understanding the Influence of Pretrial Publicity on Jurors’ Decisions and Emotions

This pilot experiment was conducted to examine ambiguity of a trial with regards to jurors’ verdicts (guilty/not-guilty). An ambiguous trial is preferred due to its ability to show biasing influences. Also investigated were the effects of positive and negative pretrial publicity (P-PTP/N-PTP) on jurors’ decisions and emotions. Participants (N=26) viewed a murder trial, provided verdicts and guilt ratings, recalled trial facts and related emotions, and completed a defendant credibility scale. These tasks were completed prior to administration of PTP, allowing for the measure of trial ambiguity. Prior to PTP, verdicts were almost equally divided between guilty (54%) and not guilty (46%), demonstrating ambiguity. Participants were randomly assigned to read either P-PTP or N-PTP and again completed the measures. After PTP exposure N-PTP jurors’ guilt ratings increased and those for P-PTP jurors decreased, having the expected effects on jurors’ decisions. N-PTP exposure resulted in increased juror anger and decreased defendant credibility; while P-PTP resulted in the defendant being viewed as more credible. Stimuli developed for this study potentially furthers the exploration of anger as a mechanism in juror decision making. Development of ecologically valid trial stimuli is an important and has potential to benefit researchers and the field of jury decision