This article provides a comprehensive review of the empirical research on jury decision making published between 1955 and 1999. In total, 206 distinguishable studies involving deliberating juries (actual or mock) were located and grouped into 4 categories on the basis of their focal variables: (a) procedural characteristics, (b) participant characteristics, (c) case characteristics, and (d) deliberation characteristics. Numerous factors were found to have consistent effects on jury decisions: definitions of key legal terms, verdict/sentence options, trial structure, jury-defendant demographic similarity, jury personality composition related to authoritarianism/dogmatism, jury attitude composition, defendant criminal history, evidence strength, pretrial publicity, inadmissible evidence, case type, and the initial distribution of juror verdict preferences during deliberation. Key findings, emergent themes, practical implications, and future research directions are discussed.
