This is in response to the letter by Josephine D. Thomas, applauding U.S. Rep. John Katko's assessment of the recent high school shooting in Parkland, Florida. Both Ms. Thomas and Rep. Katko believe that mental illness is the primary contributor to gun violence in this country, but their conclusion is not shared by experts or supported by widely accepted research.
True, some mentally ill people can be violent, but statistics show that mentally ill people are more likely to be the victims of violence, rather than the perpetrators. A 2015 study of a database of mass shooters by Columbia University found that only 52 out of the 235 killers in the database (22 percent) had mental illnesses. A 2015 study in the American Journal of Public Health found that fewer than 5 percent of gun-related killings in the U.S. between 2001 and 2010 were committed by people diagnosed with mental illness.
The book "Gun Violence and Mental Illness," published by the American Psychiatric Association in 2016, determined that mass shootings by people with serious mental illness represent only 1 percent of all gun homicides each year. A Google search will provide a more comprehensive summary of scholarly articles on this topic, if the reader is interested. But clearly, it is the consensus of experts in the field that the large majority of people with mental disorders do not engage in violence against others, and therefore most violent behaviors must be due to factors other than mental illness. Gun laws that focus on people with mental illness will only perpetuate the myth that mental illness leads to violence, thereby further stigmatizing this vulnerable demographic.