Table I presents descriptive characteristics of sub-samples with no axis I diagnosis, a substance use disorder only, comorbid substance use and non-substance use disorders, and a non-substance use axis I disorder only. As indicated in the bivariate relationships with the substance use disorder only group, defendants who had a non-substance use axis I disorder only were older, more likely to be female or married, and less likely to be involved in a male-on-male homicide or to have used a firearm in the offense.