This document discusses substance use, abuse, and dependence in forensic and correctional populations. It reports that approximately 65-70% of offenders meet criteria for substance abuse and 40-45% meet criteria for substance dependence or addiction. The document then reviews how evidence of intoxication can in some cases reduce legal culpability through defenses like diminished capacity, insanity, or automatism. However, these defenses are difficult to establish and rarely apply to typical cases. The document concludes that drug or alcohol use rarely eliminates conscious intent, though it may increase reckless behavior, and that traditional substance abuse treatment has lower success rates for offenders than typically estimated. Programs integrating treatment and supervision are more effective at reducing substance use and crime.