Offenders with an intellectual disability pose a major challenge to Intellectual Disability Service providers in the Republic of Ireland. This is especially so as no national Forensic Intellectual Disability Service currently exists.

The Forensic Intellectual Disability Working Group of the Irish College of Psychiatrists was established in order to take steps to address this issue by establishing the level of need for a Forensic Intellectual Disability Service in Ireland and developing a college position paper.

No previous study has been carried out to measure offending behaviour amongst persons with an intellectual disability attending mental health services in Ireland.

A postal survey was undertaken targeting the lead clinicians of all Intellectual Disability Psychiatry, General Adult Psychiatry and Forensic Psychiatry Services in the Republic of Ireland. This survey requested anonymous data regarding service users with an intellectual disability and offending behaviour in this population.

Data relating to 431 service users was returned. Those reported to engage in offending behaviour were predominantly young males. Assault was the most common offence type. A significant number of serious offences such as unlawful killing, sexual assault and arson were reported.

There is an urgent need for the development of a Forensic Intellectual Disability Service in the Republic of Ireland. The current efforts of the National Forensic Mental Health Service to establish such a service by the creation of a post of Consultant Forensic Psychiatrist (special interest in intellectual disability) are to be welcomed.