Dissatisfied with more traditional approaches to behavior management, psychology staff in a community-based residential treatment program for offenders with mental retardation developed and instituted a peer Jury System to deal with inappropriate resident behaviors. Behaviors were divided into eight major areas and analyzed for 5 months subsequent to the institution of the Jury System, with statistically significant improvement noted in 7 of the 8 areas and for 11 of the 12 subjects. Implications must be viewed as provisional due to the AB design, but results suggest that the system warrants serious consideration for expanded use with offenders with mental retardation.