A number of aspects of deliberation procedures also suggest that the jury process may be failing. James (1959) found that, while deliberating, jurors were not using their time effectively. Fifty percent of the jury's time was used discussing opinions and personal experiences, often only indirectly related to the trial; about 35% of their time was used considering instructions and procedural issues, with only 15% of jurors time spent deliberating on testimonial evidence.
An investigation of jury deliberation by Hawkins (1962) looked at the amount of juror participation when more then one opinion was held within the group. He found that the larger faction spoke for a much greater amount of time, and that the minority opinion was stifled. Kalven and Zeisel (1966) hypothesized that jury deliberation does not accomplish its primary task of find facts, but rather allows the majority opinion to persuade the minority to shift toward agreement.
Group discussion can even lead to improper decisions when all the jurors' opinions are in agreement. Social psychological theory predicts that once jury members discuss their opinions, and find that they all share it, the group will use this information to further reinforce their decision and will often take it to an extreme level. In their study, Myers and Kaplan (1976) investigated this issue of group polarization. In their study subjects were exposed to high and low guilt situations, subsequently being asked to give their verdict and sentence. Subjects were then placed together into a mock jury and told to have an open discussion deliberation. As expected those who had originally made low guilt decisions became increasingly lenient after deliberating, while those who held high guild opinions made increasingly severe decisions.
