Researchers have found that the vast majority of domestic mass shooters in the US have untreated psychiatric disorders.
“Without losing sight of the larger perspective that most who are violent are not mentally ill, and most of the mentally ill are not violent, our message is that mental health providers, lawyers, and the public should be made aware that some unmedicated patients do pose an increased risk of violence,” says Dr. Ira D. Glick, one of the study’s authors.
For the study, the researchers identified 155 individuals as committing a mass shooting in the US between 1982 and 2019 using the Mother Jones’ database. The database discluded ‘conventionally motivated’ crimes such as armed robbery or gang violence.
As the perpetrators died either during or shortly after the crime in most of these cases, the researchers focused on 35 cases in which the perpetrator survived and underwent criminal proceedings to assess their psychiatric state.
For each of these cases, the researchers spent hours analyzing records and interviewing the forensic psychiatrists and psychologists who examined the assailants after their crimes. They also examined court proceedings, public records, videotaped interviews as well as social media posts and writings by each perpetrator.
From their analysis, the researchers concluded that 32 of the 35 perpetrators showed signs and symptoms of clinical psychiatric disorders. They further said that 18 had schizophrenia, with ten other diagnoses including bipolar disorder, delusional disorder, personality disorder and substance-related disorders. In three cases, they had insufficient information to make a diagnosis while in four, they did not find any diagnosis.
The researchers noted that of the 28 surviving perpetrators with a psychiatric diagnosis, none received treatment prior to their crimes.
From analyzing 20 mass shooters who died at the crime scene, they were additionally able to identify eight further cases of schizophrenia, seven other diagnoses and five unknown diagnoses. None of these assailants were receiving appropriate healthcare at the time as well.
“The psychiatric disorders seen in perpetrators of mass shootings are serious brain illnesses – as much in need of proper diagnosis and treatment as heart disease or any other medical condition,” says Dr. Glick.
“We need to reduce the stigma associated with these diseases to enable patients to receive appropriate and adequate psychiatric medication and other treatments. By actually talking to patients and their significant others, we have the opportunity to save lives.”