Homicide in the context of psychosis: analysis of prior service utilisation and age at onset of illness and violence.

Abstract

Public stigma and fear are heightened in cases of extreme violence perpetrated by persons with serious mental illness (SMI). Prevention efforts require understanding of illness patterns and treatment needs prior to these events unfolding. To examine mental health service utilisation by persons who committed homicide and entered into forensic care, to investigate the adequacy of mental healthcare preceding these offences. Forensic patients across two mental health hospitals in Ontario with an admitting offence of homicide between 2011 and 2021 were identified (n = 112). Sociodemographic, clinical and offence-related variables were coded from the health record and reports prepared for the forensic tribunal. Most patients (75.7%) had mental health contacts preceding the homicide, with 28.4% having a psychiatric in-patient admission in the year prior. For those with service contacts in the year preceding, 50.9% had had only sporadic contact and 70.7% were non-adherent with prescribed medications. Victims were commonly known to the individual (35.7%) and were often family members in care-providing roles (55.4%). Examination of age at onset of illness and offending patterns suggested that most persons admitted to forensic care for homicide act in the context of illness and exhibit a low frequency of pre-homicide offending. Many individuals admitted to forensic care for homicide have had inadequate mental healthcare leading up to this point. Effective responses to reduce and manage risk should encompass services that proactively address illness-related (e.g. earlier access and better maintenance in care) and criminogenic (e.g. substance use treatment, employment and psychosocial supports) domains.