Justice needs a new blindfold: A review of mock jury research.

Studies on factors that may influence jurors' verdicts are reviewed. These factors include characteristics of the jurors, characteristics of the victim and defendant, judges' instructions regarding pretrial publicity and inadmissible evidence, number and severity of decision alternatives, jurors' conception of guilt, and size of the jury and its decision rule. Data have indicated that many extra-evidential factors contribute to mock jurors' verdicts. However, the applicability of these results is limited by the many methodological and sampling problems inherent in the studies. It is suggested that efforts to develop methods of minimizing biases would be most successful if undertaken conjointly by legal experts and social scientists. It is beyond argument that a variety of extra-evidential factors influence jury decisions. Whether or not this should be so is a highly debated issue that is beyond the scope and purpose of this review (for discussions of the positions involved, see Brooks & Doob, 197S, and Kadish & Kadish, 1971). Reviewing judges' written reports of over 3,500 real criminal cases, Kalven and Zeisel (1966) found that judges and juries disagreed on the verdicts in approximately 20% of the cases, with most disagreements in the direction of jury leniency. The judges indicated that the reasons for the disagreements included characteristics of the defendant and victim, the type of crime prosecuted, and the jury's evaluation of that crime. Although it is possible that the judges' self-reports were somewhat biased, studies by Reed (1965) and Wolfgang and Reidel (1973) have reached conclusions similar to those of the judges. Reed (1965) documented individual differences in juror's deliberation behavior via self-report questionnaires administered to a sample of Louisiana jurors. He found significant differences between guilty and not guilty votes, as a function of juror birthplace, previous jury duty, and socioeconomic status.