Victim relations and factors triggering homicides committed by offenders with schizophrenia

Abstract

In Western countries about 10 – 15% of those convicted of homicide suffer from a psychotic disorder. Victims are most often from the offender's immediate network, such as family members and friends. Delusions and/or hallucinations have an important role in violent behaviour, as does coexistent alcohol or drug abuse. In this study, all 48 homicides from 1992 – 2000 committed by offenders in Sweden diagnosed with schizophrenia were studied in order to identify possibly triggering factors related to victim relations. Nine of the 52 victims were strangers to the offender. In 54% of cases, the homicides were associated with obvious delusions and/or hallucinations. Among offenders with family victims 72% suffered from obvious delusions and/or hallucinations, as compared to 43% of offenders with non-family victims. Of the offenders, 79% were known to psychiatric services, but at the time of the crime only 33% had any ongoing contact. Despite 48% having been prescribed antipsychotic drugs, no more than two individuals were actually taking their medication. The offenders who had killed members of their biological families were seldom intoxicated and few had earlier convictions for violent crime. The mental health care services have a major responsibility to prevent homicides and violent crimes being committed by those with schizophrenia.