A public health perspective on violent offenses among persons with mental illness

Objective: This study reanalyzed existing data to assess the extent to whic h persons with mental illness might contribute to criminal violence in the community, Methods: Data were examined from a representative sample of 1,15 1 remanded offenders who underwent a full structured diagnostic interview t hat was used to provide one-month prevalence rates of mental illnesses as d efined by the Structured Clincal Interview for DSM-III-R. Diagnoses of inte rest were mood, psychotic, anxiety, psychoactive substance use, adjustment, and miscellaneous axis I disorders and arris II personality disorders. Cri minological data describing the number of offenses against persons and prop erty and the number of victimless crimes were abstracted from police arrest reports and warrants. A violent crime was defined as any crime against a p erson. Results: The one-month prevalence of major mental and substance use disorders of newly admitted inmates was 61 percent. About 3 percent of viol ent offenses could be attributed to individuals who had a principal diagnos is of any non-substance use-related disorder. An additional 7 percent of vi olent offenses could be attributed to individuals who had a primary diagnos is of a substance use disorder. Conclusions: The results of the study suppo rt the hypothesis that people with mental and substance use disorders are n ot major contributors to police-identified criminal violence. Public percep tions of mentally ill persons as criminally dangerous appear to be greatly exaggerated.