Mental illness is no small factor in mass killings

Grant Duwe & Michael Rocque, LA Times - Efforts to downplay the role of mental illness in mass shootings are simply misleading. There is a clear relationship between mental illness and mass public shootings.

At the broadest level, peer-reviewed research has shown that individuals with major mental disorders (those that substantially interfere with life activities) are more likely to commit violent acts, especially if they abuse drugs. When we focus more narrowly on mass public shootings — an extreme and, fortunately, rare form of violence — we see a relatively high rate of mental illness.

According to our research, at least 59% of the 185 public mass shootings that took place in the United States from 1900 through 2017 were carried out by people who had either been diagnosed with a mental disorder or demonstrated signs of serious mental illness prior to the attack. (We define a mass public shooting as any incident in which four or more victims are killed with a gun within a 24-hour period at a public location in the absence of military conflict, collective violence or other criminal activity, such as robberies, drug deals or gang turf wars.)

Mother Jones found a similarly high rate of potential mental health problems among perpetrators of mass shootings — 61% — when the magazine examined 62 cases in 2012.