Suggested adaptations to the HCR-20 for offenders with intellectual disabilities

Abstract

Although there are a number of well-researched structured professional judgement (SPJ) instruments available for purposes of risk assessment of violent offenders none of these instruments provide explicit rules for the differential assessment of intellectually disabled (ID) offenders. That is, there are no generally accepted guidelines for the application of the standard items in commonly used SPJ instruments to ID clients. As a result, researchers and clinicians who have found evidence that SPJ instruments are valid with ID offenders have adapted the items in these instruments in idiosyncratic ways and, to date, have not always been clear as to how this was done for the purposes of their research. For example, there is evidence that the Historical-Clinical-Risk-20 (HCR-20) (Webster, Douglas, Eaves & Hart, 1997) is valid for violent offenders with ID (e.g., Lindsay et al. 2008), but these authors do not explicitly explain how they adapted the HCR-20 in their study. The present chapter aims to provide some guidelines for the use of the HCR-20 primarily with ID individuals who have been charged with non-sexual violent crimes. Furthermore, we would also propose that the principles and strategies elucidated in this chapter applied in risk assessment of offenders with intellectual disabilities could potentially be adapted to provide an assessment framework for people with intellectual disabilities who, though not ever (or at least not currently) involved in the criminal justice system, exhibit behaviours labelled as challenging. That is, 'culturally abnormal behaviours of such an intensity, frequency or duration that the physical safety of the person or others is likely to be placed in serious jeopardy, or behaviour which is likely to seriously limit the use of, or result in the person being denied access to ordinary community facilities' (Emerson, 2001). While some ID individuals may commit violent behaviour, such behaviours are not always legally consequenced owing to issues regarding mental capacity and intent-both of which are somewhat beyond the scope of this chapter-although both are addressed briefly under item 'H1' of the HCR-20. (PsycINFO Database Record (c) 2016 APA, all rights reserved)