How may alternative drug policy settings influence criminal charges? A longitudinal study of cannabis patients and a general population sample

Background: This study examines criminal charges amongst cannabis use disorder (CUD) patients and a matched sample in a setting of drug criminalization, and simulates the effect of policy changes on the proportion obtaining a criminal record and on the number of charges for those being charged. Methods: All CUD patients entering specialist treatment in Norway in 2009-2010 (n=3,951) were included from the Norwegian Patient Registry and a random sample matched on age and gender drawn from the general population by Statistics Norway (n=7,902). Data were linked to the Norwegian Crime Registry (2009-2014). The nature and extent of all charges were examined. A static simulation exercise assessed the hypothetical effect on charges if a) all charges for use and possession of illicit drugs were eliminated ("decriminalization") and b) in addition, all charges for cultivation, manufacturing, and sales were eliminated ("legalization"). Results: Two thirds (66%) of patients and 12% of matched sample were charged during the observation period. While the most common offence for patients was drug law violations (52%), relatively few (14%) had no other charges. Road traffic violations was the most common offence for the matched sample and 1.2% were charged with drug offences only. The mean number of charges were 9 for the patients and 3 for the matched sample. Simulations suggest that decriminalization may decrease the proportion being charged by 8% for patients and 4% for the matched sample under "decriminalization", compared to 24% and 11%, respectively if all drugs were legalized. The number of charges for patients and non-patients would drop by 23% and 13% respectively, while legalization may decrease the number of charges by 46% and 25%, respectively. Conclusion: The simulations suggest that the impacts of decriminalisation and legalisation on the proportion being charged are relatively modest, while the policy changes are likely to lead to substantial reductions in the number of charges for both the patient and non-patient groups.