Adolescent use of illicit drugs and adult offending: a Swedish longitudinal study.

The main aim of this study was to examine the role of illicit drug use before the age of 18 years in developing a criminal career. The study included 7577 18-year-old men conscripted for military service in Stockholm County in 1969/1970. At enrolment they answered questions regarding alcohol and illicit drug use, social background, behavioural factors and health. Data on adult and adolescent criminality were obtained from official registers from the age of 15 to the age of 43. Subjects with self-reported drug use were registered significantly more often (p <or= 0.0001) for future drug offences and other non-drug offences than were subjects with no drug use at all. Irrespective of the number of adolescent offences, if subjects also reported illicit drug use in adolescence, their adult criminal activity was considerably higher than if they had not used any drugs during adolescence. This was also true when examining other risk factors. Generally, adolescent illicit drug use was a risk factor over and above common risk factors for adult criminality. Early prevention of illicit substance use and criminality in adolescence is important in hindering a future criminal career.