Forensic Risk Assessment in Intellectual Disabilities: The Evidence Base and Current Practice in One English Region

Abstract

The growing interest in forensic risk assessment in intellectual disability services reflects the perception that deinstitutionalization has exposed more people to a greater risk of offending. However, ‘risk’ and the related idea of ‘dangerousness’ are problematic concepts because of connotations of dichotomous definition, stability and predictability. Assessment instruments in mainstream forensic psychiatry often combine actuarial and clinical data, and increasingly stress the dynamic nature of risk as well as the importance of situational and accidental triggers. Despite this increasing sophistication of research in mainstream forensic psychiatry, the ability to predict future offending behaviour remains very limited. Furthermore, actuarial predictors developed in studies of psychiatric or prison populations may not be valid for individuals with intellectual disabilities. Offending behaviour among people with intellectual disabilities is also hard to circumscribe because it often does not invoke full legal process or even reporting to the police. In order to discover how such problems were reflected in practice, a survey of providers in the North-west Region of England was undertaken. Seventy out of 106 providers identified as possibly relevant to this inquiry responded to a short postal questionnaire. Twenty-nine (42%) respondents – mainly in the statutory sector – reported operating a risk assessment policy relating to offending. The number of risk assessments completed in the previous year varied from none to ‘several hundred’. Providers reported three main kinds of problems: (1) resources or service configuration; (2) interagency or interdisciplinary cooperation or coordination; and (3) issues relating to the effectiveness, design and content of assessment.