Alcohol and/or drug use prior to the offense is reported by 60 percent of the offenders. Offenders who used alcohol only make up the largest group among those who used drugs and/or alcohol. The group that used alcohol and drugs prior to the offense is of particular interest. This group represents young offenders who are extensively involved in psychoactive substances, exceeding all other groups. The emergence of this group may signify a trend toward more psychoactive substance use among offender groups and, as such, warrants further investigation. Since existing theoretical explanations focus on either the alcohol-crime or the drug-crime nexus, new theoretical explanations for the alcohol-drug-crime nexus need development. Finally, information on the alcohol and drug offender group suggests that intervention strategies must consider multiple drug use and the special characteristics of offenders with these problems. (Publisher abstract)