Risk of criminal justice system involvement among people with co-occurring severe mental illness and substance use disorder.

While there are documented risk factors for criminal justice system involvement (CJSI) among persons with severe mental illness, little is known about risk for CJSI among people with co-occurring severe mental illness and substance use disorders. Using logistic regression, we identified sociodemographic and clinical risk factors that most increase risk of CJSI among people with co-occurring disorders (N = 10,855: National Survey of Drug use and Health, 2006-2014), and examined whether co-occurring disorders increase CJSI risk and risk of violent offenses in relation to severe mental illness alone versus substance use disorder alone. Seventeen percent of people with co-occurring disorders in our study were arrested and booked for breaking the law in the past year. At heightened risk were males, Blacks (relative to Whites), younger people, people with less education, divorced or separated individuals (relative to married), the unemployed, persons in the largest households (6 or more people, relative to one person), people in substance abuse treatment, and persons with certain drug use disorders (e.g., both alcohol and marijuana, relative to alcohol only). At reduced risk were Asians (relative to Whites), people with the highest incomes, and people with marijuana use disorders (relative to alcohol). In relation to people without severe mental illness or substance use disorder, those with co-occurring disorders were 7.47 times as likely (CI = 6.56-8.51, p < .001) to be arrested and booked for breaking the law in the last 12 months, while those with severe mental illness (only) were 1.84 times as likely (CI = 1.64-2.08, p < .001) and those with substance use disorder (only) were 5.32 times as likely (CI = 4.86-5.83, p < .001). After using our findings to identify people who are at greatest risk for CJSI, preventative interventions could be offered.