In a piece for the American Association of Medical Colleges (1/26/23), John Rozel and Jeffrey Swanson cited a 2018 study that found that less than 5% of mass shooters had any record of a gun-disqualifying mental health adjudication, like involuntary hospitalization:

Indeed, if serious mental illnesses suddenly disappeared, violence would decrease by only about 4%. More than 90% of violent incidents, including homicides, would still occur.

They added, “The real story—and the real need—regarding mental illness and violence is suicide.”

[…]

Locking people like Card in mental health facilities doesn’t automatically cure them. And considering mentally ill people are far more likely to be the victims than the perpetrators of violence, it certainly does not adequately address the mass shooting crisis in this country.