Accuracy of Verdicts under Different Jury Sizes and Voting Rules

Juries are a fundamental element of the criminal justice system. In this article, we model jury decision making as a function of two institutional variables: jury size and voting requirement. We expose the critical interdependence of these two elements in minimizing the probabilities of wrongful convictions, of wrongful acquittals, and of hung juries. We find that the use of either large nonunanimous juries or small unanimous juries offers alternative ways to maximize the accuracy of verdicts while preserving the functionality of juries. Our framework, which lends support to the elimination of the unanimity requirement in the presence of large juries, helps appraise US Supreme Court decisions and state legal reforms that have transformed the structure of American juries.