Abstract: | Substance abuse is related to offending and substance abuse treatment has been associated with reductions in criminal behavior. This cohort study aimed to explore the relationship between participation in substance abuse interventions and general criminal recidivism among offenders with a combination of mental health problems and substance use problems. In total, 150 Swedish offenders with self-reported mental health and substance use problems were followed for approximately three years with regard to participation in substance abuse interventions and criminal recidivism. Participants with at least three planned visits to specialized outpatient substance abuse clinics had a substantially reduced risk of reoffending as compared to those with fewer than three such visits (HR = 0.47, 95% CI 0.29–0.77). For those with at least three planned visits, general criminal recidivism was reduced by 75% during periods of participation in outpatient visits, as compared to periods of non-participation (HR = 0.25, 95% CI 0.11–0.60). For offenders with mental health problems and substance use problems, outpatient substance abuse interventions could be regarded as important from a clinical risk management perspective, and be encouraged. |