First, recent empirical data suggest that progressively smaller juries are less likely to foster effective group deliberation. At some point, this decline leads to inaccurate fact-finding and incorrect application of the common sense of the community to the facts. Generally, a positive correlation exists between group size and the quality of both group performance and group productivity. A variety of explanations have been offered for this conclusion. Several are particularly applicable in the jury setting. The smaller the group, the less likely are members to make critical contributions necessary for the solution of a given problem. Because most juries are not permitted to take notes, memory is important for accurate jury deliberations. As juries decrease in size, then, they are less likely to have members who remember each of the important pieces of evidence or argument. Furthermore, the smaller the group, the less likely it is to overcome the biases of its members to obtain an accurate result. When individual and group decisionmaking were compared, it was seen that groups performed better because prejudices of individuals were frequently counterbalanced, and objectivity resulted. Groups also exhibited increased motivation and self-criticism. All these advantages, except, perhaps, self-motivation, tend to diminish as the size of the group diminishes. Because juries frequently face complex problems laden with value choices, the benefits are important and should be retained. In particular, the counterbalancing of various biases is critical to the accurate application of the common sense of the community to the facts of any given case.

Second, the data now raise doubts about the accuracy of the results achieved by smaller and smaller panels. Statistical studies suggest that the risk of convicting an innocent person rises as the size of the jury diminishes….

Third, the data suggest that the verdicts of jury deliberation in criminal cases will vary as juries become smaller, and that the variance amounts to an imbalance to the detriment of one side, the defense.