Much of the discrimination towards persons with mental illness comes from the idea that people with mental illness tend to be violent. This link between mental illness and violence is sometimes perpetuated by the news and entertainment media. This presumption of violence may provide justification for victimizing persons with mental illness. Members of the public also tend to exaggerate both the association between mental illness and violence and their own personal risk. In fact, using data from a study conducted in the United States, the attributable risk (the overall effect that a factor has on the level of violence) for persons with mental illness was 4.3%, meaning that violence in the community could be reduced by 4.3% if major mental disorders could be eliminated. By contrast, the attributable risk for persons with a substance disorder was 34%. A Canadian study surveyed 1,151 newly detained criminal offenders representing all individuals in a particular geographic area. Three percent of the violent crimes of this group were attributable to persons with major mental disorders, such as clinical depression and schizophrenia. Although these studies show that most patients with mental illness are not violent, studies also show that if a person with mental illness becomes violent, it is largely because they showed other factors associated with violence, and mental illness alone is not a significant factor of future violence. Predictors of violence are significantly associated with being younger than 43, being a male, having an annual income below $20,000, having parents with a history of criminal activity, having a history of violence or juvenile detention, witnessing parents physically fighting, substance abuse, being victimized, divorced, separated or unemployed, and having bipolar or depression with substance abuse. Absent from this list is mental illness by itself. Although there is a small possibility that persons with mental illness may become violent, most people who are violent are not mentally ill, and most people who are mentally ill are not violent.
Reprinted from April, 2010