Comparison of intellectually disabled offenders with a combined history of sexual offenses and other offenses versus intellectually disabled offenders without a history of sexual offenses on dynamic client and environmental factors

•Minimal differences of ID mixed sex and non-sex offenders on dynamic client factors.•Minimal differences of ID mixed sex and non-sex offenders on environmental factors.•There are possible common factors for a more general theory of offending behavior. Sexually offensive behavior is prevalent among individuals with intellectual disabilities (ID) and many sex offenders also commit other offenses such as vandalism or assault. We examined the differences between sex offenders with ID and a history of combined sex and other types of offenses (mixed sex offenders) versus offenders with no history of sexual offenses (non-sex offenders). Dynamic client and environmental factors were measured using the Adult Behaviour Checklist (ABCL) and the Risk Inventarization Scale on Sexually Offensive Behavior of Clients with intellectual disabilities (RISC-V). Item, subscale, and total scores were then compared for the two groups. Most of the comparisons did not reveal significant differences between the two groups. The findings call for a general theory of offending behavior to explain the absence of differences between the mixed sex offenders and non-sex offenders with ID.