Long-term Impacts of the Swiss Heroin Prescription Trials on Crime of Treated Heroin Users

During the Swiss heroin prescription trials (PROVE, 1994–1996), over 1,000 heavily addicted heroin users were recruited into the program. While short- and medium-term effects of the program had been thoroughly assessed earlier, only a small body of data on the long-term effects on treated subjects was available. Data on program dropouts were particularly scarce. In order to partially fill that gap, police records of all participants were collected in summer 2000. Based on these data, the present paper focuses on the long-term effects (up to 48 months after admission) of heroin maintenance on criminal involvement and, to some extent, on addictive behavior. Results suggest that heroin prescription causes a strong and stable decrease in criminal involvement of most patients. Similar patterns of desistance are observed for a broad range of offenses and across different subpopulations of patients. Although the most pronounced decrease in criminal involvement is observed in the group of those treated permanently, treatment effects seem to hold in the post-treatment period. In particular, post-treatment rates of records related to use/possession of heroin remain comparatively stable, indicating that most program dropouts do not reengage in (public) use of illegal heroin. Additional data suggest that such stabilization is mainly related to the ability of the program to redirect the majority of patients towards alternative treatments once they left the treatment program.