According to recent research, approximately 50 percent of people with severe mental illness and substance abuse problems are dual disorder individuals have had previous contact with the criminal justice system. The standard treatment for dual disorder individuals in the United States is parallel treatment. Assertive Community Treatment (ACT) is an evidence-based model for providing services to those with severe mental illness. Many clinicians and researchers advocate that integrated treatment (IT) models be implemented for treating dual disorder individuals. This study evaluated the effectiveness of different treatment models and also estimated the effect of the characteristics of the people in the models on criminal justice outcomes. The study also tested for correlations between criminal justice outcomes and other outcome variables. The study consisted of 196 eligible participants where a baseline interview was conducted. In summary, although ACT and IT programs have produced better outcomes than other management approaches in terms of hospitalization, housing, mental health, and sometimes substance abuse, clinicians should not expect that these positive outcomes will necessarily extend to criminal behavior. Additional research is recommended to evaluate the effects of combining judicial reforms with specific mental health interventions targeted at criminal behavior of dual disorder clients. Tables, references