Adults with autism spectrum disorder and the criminal justice system: An investigation of prevalence of contact with the criminal justice system, risk factors and sex differences in a specialist assessment service

The behavioural and cognitive difficulties of some adults with autism spectrum disorder (ASD) may increase their risk of contact with the criminal justice system (CJS) as a potential suspect. There has been limited investigation of ASD and offending and available evidence is mixed. A retrospective review was completed of medical records of 1570 adults (17-75 years old) who were referred for an ASD assessment over a 17-year period (April 2003 to February 2020). Of the adults diagnosed with ASD, 23% had previous contact with the CJS. Being male or diagnosed with co-occurring attention-deficit hyperactivity disorder (ADHD) and/or psychotic disorder were risk factors for CJS contact. However, the rates of contact with the CJS or for specific offences in the ASD group were never higher than adults referred to our service but not diagnosed with ASD. We did not include a general population comparison group, therefore cannot say how rates of CJS contact in ASD compare with the general population. Further health services research for adults with ASD is warranted, as modifying the treatable risk factors (i.e. ADHD) could reduce contact with the CJS. In addition, joint working between CJS and mental health services could reduce the risk of adults with ASD having CJS contact. Lay abstract There has been growing interest in offending and contact with the criminal justice system (CJS) by people with autism spectrum disorder (ASD). However, it is not clear whether people with ASD offend more than those without ASD. Studies have started to look at whether there are particular offences people with ASD are more likely to commit and whether there are any factors that can affect whether someone comes into contact with the CJS as a potential suspect. This study looked at the patients who attended an ASD diagnostic service over a 17-year period to see the rate of contact with the CJS of those who were diagnosed with ASD and whether there were any particular factors that might increase the risk of CJS contact. Nearly a quarter of the ASD group had some contact with the CJS as a potential suspect. Factors that seemed to increase whether someone with ASD was more likely to have contact with the CJS were being male, being diagnosed with ADHD, and being diagnosed with psychosis. This study is one of the largest studies to investigate the rate of CJS contact as a potential suspect in a sample of adults with ASD in an attempt to give a clearer picture of what might influence someone with ASD to engage in offending behaviour in order to try to see what mental health services can offer to reduce the likelihood of someone with ASD coming into contact with the CJS, for example, treatment for another condition or support.