Mock jurors' insanity defense verdict selections: The role of evidence, attitudes, and verdict options

A mock insanity defense trial was presented to 140 college undergraduates by means of an audiotape and synchronized slides. Participants answered a series of questions regarding the case and their predeliberation verdict selections. Consistent with prior research,jurors who selected a guilty verdict neither believed that the defendant could be rehabilitated nor that he suffered from some mental disease or defect. Jurors who opted for a guilty verdict held favorable attitudes toward the death penalty, were crime-control oriented, and held unfavorable attitudes toward the insanity defense. Jurors who rendered a Guilty But Mentally III verdict differed significantly in their evaluations of the defendant's mental status. Mean ratings for jurors reaching this verdict were intermediate between the ratings of jurors reaching Not Guilty by Reason of Insanity and guilty verdicts. Although jurors attitudes and their evaluations of the evidence were both important correlates of verdict selection, evaluation of the evidence was weighted more heavily in the function discriminating among verdicts.