The extent to which the personal characteristics of individual mock jurors affect participation and influence with other jurors within the deliberation process was the focus of this investigation. A predeliberation locus of control measure, along with two conditions of jury composition (heterogenous vs homogenous with respect to the locus of control measure) were used to investigate interactions among sentencing severity, persuasiveness in deliberation, and demographic characteristics among 96 jurors. Results indicated that group sentences were significantly more severe than predeliberation sentences and that postdeliberation shifts were significantly more pronounced for the heterogenous juries than for the homogeneous juries.