Jury: Behavioral Aspects

Public praise and criticism for the jury have a long history, and high profile jury trials are a staple of modern press coverage. However, it is only in the past forty years that researchers have published systematic empirical studies of jury behavior. Study of the jury is a particularly thorny project because the jury speaks publicly only through its verdict. At the end of the trial the jury retires to deliberate in the privacy of the jury room. It emerges occasionally to ask a question, but more commonly, only to report its verdict.

The jury in the United States gives no explanation for its verdict and the jurors can return to their pretrial lives without revealing any information about how they arrived at their decisions. Research on the jury, as a result, has relied on a variety of indirect methods, each with strengths and limitations: (1) archival studies of jury case characteristics and verdict patterns (records provide information on large samples of cases, but courts record a limited number of variables); (2) post-trial interviews with jurors (the jurors are reporting on the actual process of reaching a verdict, but what they report is limited to what jurors noticed, accurately recorded, remember, and are willing and able to report); (3) surveys of other trial participants, such as judges and attorneys (these respondents are informed court observers, but they have only indirect information on jury behavior and their reports may be influenced by the verdict); (4) field experiments (these can offer strong evidence on the impact of a legal reform like juror note-taking, but they provide little information on process and are hard to implement successfully); and the most common approach; (5) simulation experiments (simulations are strong on process information and provide unambiguous causal inference, but generalizability of findings depends on correspondence with dynamics of real jury behavior). By combining these various approaches, researchers have compiled a nuanced, although incomplete, picture of jury behavior.