A relatively high proportion of people detained in forensic psychiatric hospitals have intellectual disabilities (up to 3000 people in the UK; Royal College of Psychiatrists, 2013), and people with intellectual disability are significantly over-represented among those psychiatric patients with long lengths of hospital stay (CQC, 2013; Vollm, 2015). People with mild to borderline intellectual disabilities are also prevalent in the UK prison system.

Although the relationship between intelligence and offending is complex, lower intelligence is a known actuarial risk factor for offending behaviour. Studies, which have investigated the prediction of re-offending risk in populations with intellectual disability, have nevertheless found lower rates of recorded re-offending compared to those in mainstream forensic populations (e.g. Gray et al., 2010). The relatively high rate of ‘offending-like’ behaviour, which is not processed through the criminal justice system in people with intellectual disability makes risk prediction a more complex exercise with this group of people. It also makes outcomes measurement more difficult.

This paper will give an overview of the current research evidence and clinical practice in the field of risk assessment, risk management and outcome measurement with offenders with intellectual disability. It will summarise the findings of a recent NIHR funded systematic review by the author, which pertains to this area, and will point to future developments in the field.