Forensic psychiatry for people with learning disability

The traditional debate about the association between mental deficiency and crime requires gross simplifications of the concepts of mental disorder and of criminal behaviour. However, a focus on serious interpersonal offences and property offences, including arson, is a reasonable starting point. It would be pointless to include offences which required a high degree of sophis tication or ability. There have, however, been some good recent studies of specific groups. There is evidence that for people with learning disability, who are receiving services, the incidence of offending is low.Lyalletal (in press) found that 2%of 358adults with learning disability, living in residential homes or attending day services, had contact with the police in 1992.On the other hand, they found that there was a marked tendency to tolerate and to under-report offences. Harris (1993) has reported the prevalence of aggressive behaviour in a health district. He also included those placed outside the district because of their behaviour. The overall prevalence of aggressive behaviour among people with learning difficulties was 17.6%. The lowest rate was identified among day facilities (9.7%) and the highest in hospitals (38.2%). The prevalence in schools for children with severe learning diffi culties was 12.6%.In the aggressive sample, men outnumbered women by about 2:1, however this difference vanished in hospitals and schools. In a thoughtful discussion, the following points were emphasised. Account must be taken of the degree of aggression, indeed in this study the risks of serious injury were found to be 'very low'. Physical