Citation: 435 U.S. 223 (1978).
One-Sentence Takeaway: A criminal trial by a five-person jury violated the Sixth and Fourteenth Amendments, as juries smaller than six diminish the reliability of verdicts and the representativeness of community viewpoints.
Summary: A 1978 U.S. Supreme Court opinion in which the Court held that a state could not conduct a criminal trial with less than six jurors and doing so violated a criminal defendant’s right to a jury trial guaranteed by the Sixth Amendment.
The Court supported its ruling with empirical research showing a correlation between jury size and the accuracy of the results. The Court noted, “[a]s 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 is seen that groups performed better because prejudices of individuals were frequently counterbalanced, and objectivity resulted.” Id. at 234.
Reference Desk
Sanford v. U.S., 586 F.3d 28 (D.C. Cir. 2009):
In Ballew the Supreme Court held that five-person juries for non-petty offenses violated the Sixth Amendment right to a criminal jury trial, a right that previously had been incorporated through the Fourteenth Amendment to apply to the States. Relying on empirical studies of juries and group dynamics more generally, the Court concluded that there was a constitutional deficiency with juries that were too small. The studies showed that, in general, as group size decreased beyond a certain threshold, so did the quality of deliberation. When juries in particular were smaller, the studies raised doubts about the accuracy and consistency of the results achieved. The studies further indicated that smaller juries resulted in fewer minority viewpoints being represented, and that jurors holding those viewpoints were less likely to speak up during deliberations. Finally, the studies indicated that representation of minority groups decreased with decreasing panel size. Given the Sixth Amendment’s requirement of “an impartial jury of the State and district wherein the crime shall have been committed,” the Court was concerned that juries with fewer than six members would limit “the opportunity for meaningful and appropriate representation” of a “cross-section of the community.”