Not Criminally Responsible on Account of a Mental Disorder for a Homicide: Examining Gender Differences to Identify Opportunities for Early Prevention

This study examined the characteristics and healthcare service trajectories of 98 men and 29 women found not criminally responsible on account of mental disorder (NCRMD) for a homicide in Canada using data from Criminal Review Boards and police reports, as well as health administrative databases for a subsample in Québec ( n = 51). Three quarters of the sample had no prior criminal justice involvement, and half had contact with mental health services in the year preceding the offense. Victims were usually known to the people found NCRMD for a homicide (83%). Women were more likely to have a mood disorder as primary diagnosis, and less likely to have displayed overt psychotic symptoms at the time of the offense. They were more likely to be found NCRMD following an event of intrafamilial violence, typically involving their children. Women were more likely to commit a homicide shortly after seeking mental health services, with an average of 18.6 days elapsing since service contact compared to an average of 101.3 days for men. Overall, these findings signal unsuccessful attempts by a subgroup of individuals, particularly women, suffering from severe mental illness to seek timely, appropriate services. Strategies for prevention, including early intervention and services, are discussed.