Knowledge updating in jurors : cognitive load affects juror decision making.

Mock jurors read a trial summary describing the armed robbery of a convenience store and rendered a verdict. Then, half of the jurors viewed an exculpatory videotape of the robbery; the remaining jurors completed an unrelated task. All jurors voted again. Those who watched the video were less likely to vote guilty at Time 2. In Experiment 2, we manipulated cognitive load by having the jurors memorize a series of numbers during summary reading and videotape viewing. Jurors in the cognitive load condition were less likely to vote guilty after reading the summary and were less likely to modify their verdict after viewing the exculpatory video. In Experiment 3, we manipulated cognitive load by adding extraneous details to the case summary and limiting the time available to read the summary. The results confirmed those of Experiment 2. These results are consistent with a resource-limited knowledge updating view of juror decision-making.