Anders Håkansson, Virginia Jesionowska

The present study aimed to study the associations between substance use patterns and types of crimes in prisoners with substance use problems, and specifically whether substance use patterns were different in violent offenders. Interview data of prisoners with substance use problems (N=4,202, mean age 33.5 years, SD 9.8), derived from the Addiction Severity Index, were run against criminal register data on main types of crimes in the verdict. In binary analyses, compared to those with acquisitive and drug crimes, violent offenders had lower prevalence of illicit drugs and homelessness, but higher prevalence of binge drinking, and higher prevalence of sedative use than clients sentenced with drug crimes. Clients with violent crime had lower prevalence of injecting drug use, compared to all other crimes. In logistic regression, binge drinking and sedatives were positively associated with violent crime (as opposed to non-violent crime), whereas heroin, amphetamine, cocaine, and injecting drug use were negatively associated with violent crime. Among violent offenders only, sedatives tended to be associated with fatal violence (p=0.06), whereas amphetamine, homelessness, age, and (marginally significant, p=0.05) heroin were negatively associated with fatal violence, as opposed to non-fatal violence. Treatment and risk assessment in violent perpetrators with substance use may need to address sedatives and alcohol specifically. Limitations of the study are due to self-reported and cross-sectional data and because a large majority of the prison sample studied here are men.