One important limitation of previous research involving measures of bias is that they rely heavily on brief methods of conveying trial information (case summaries) and participants typically do not deliberate as juries before rendering verdicts. In the present study, 183 jury-eligible college students completed the Pretrial Juror Attitudes Questionnaire (PJAQ) and the Juror Bias Scale, watched a videotaped simulated armed robbery trial, and rendered verdicts both before and after deliberating as juries. The results indicate that the PJAQ, and especially the subscales of System confidence and Conviction proneness, significantly predicts pre-deliberation verdicts as well as verdict change (i.e. the shift in verdicts from pre-to post-deliberation). Moreover, the PJAQ provides incremental predictive validity over a more commonly used measure of pretrial bias (the Juror Bias Scale) for pre-and post-deliberation verdicts, as well as providing incremental predictive validity with respect to a juror's tendency to change his/her verdict as a function of the deliberation process. Specifically, bias is associated with a greater probability of verdict change, regardless as to whether that bias reflects a pro-prosecution or pro-defense position. The implications these results have for the importance of pretrial attitude on juror judgments and the deliberation process are discussed.