Sex offender risk assessment is complex, especially when this concerns intellectually disabled sex offenders (IDSOs). This subgroup of sex offenders require specific attention in relation to risk assessment, yet tools designed for non-IDSOs continue to be applied to them.
This review examines the Risk Matrix 2000, a static risk assessment tool that is designed to assess risk of sexual and violent recidivism. Its validity, reliability and practical utility for sex offenders with intellectual disabilities are explored.
Appraisal of this tool indicates that although empirical support exists for its use with sex offenders without intellectual disability, the Risk Matrix 2000 is not established as reliable or valid for use with IDSOs. Although less extensively empirically examined than the Risk Matrix 2000, the ARMIDILO-S, which incorporates protective factors as well as risk factors, shows superior predictive validity to the Risk Matrix 2000 with IDSOs and its use may therefore be more ethically defensible. Specific testing of actuarial (and other types) of tools is required on IDSOs.
Further empirical support is needed to support the use of the Risk Matrix 2000 with IDSOs, and other risk assessment tools that are designed specifically for this subgroup of sex offenders may be more appropriate to use. The Risk Matrix 2000 and its resulting risk groups should not be relied upon for IDSOs and its continued use on this subgroup is questionable.