Mental Illness Not Behind Majority of School Shootings, Study Finds

Researchers analyzing the motivations behind mass school shootings have concluded that in the majority of cases severe mental illness wasn’t a contributing factor. The study, published in the Journal of Forensic Sciences by a team at Columbia University Irving Medical Center and the New York State Psychiatric Institute (NYSPI), suggests that more attention should be paid to cultural and social factors uniquely driving academic mass killings.

“A distinct phenomenon”

“Our findings suggest that mass school shootings are different from other forms of mass murder, and that they should be looked at as a distinct phenomenon,” said Dr. Ragy R. Girgis, who co-led the research alongside Dr. Gary Brucato. Girgis leads a center specializing in the treatment of teens at risk for mental health conditions like schizophrenia and psychosis. The research is thought to be the largest such investigation of mass school shootings ever published, taking in data from 83 different atrocities from around the world.

Girgis and colleagues used data from a repository called the Columbia Mass Murder Database (CMMD), created to better understand the link between severe mental ill-health and mass shooting events.  

The CMMD contains information on nearly 15,000 killings recorded online or in print between 1900 and 2019. The team’s review of school shootings found that semi- and fully automatic firearms were the most common weapon of choice in mass killings.

Almost half (47.6%) of the school killings analyzed took place in the US, as did nearly two-thirds (63.2%) of those involving guns. Every single mass murderer in the database was male, and 66.7% were Caucasian. In 80.7% of shootings, and 68.0% of killings not involving firearms, no severe mental illness was found. Nearly half of the perpetrators killed themselves after the shooting, leading the authors to question whether killers view their actions as a “kind of final act” – a factor that may alter how policy is designed around killings and how police forces should intervene.

Breaking down stigma

While the findings are not predictive of likelihood to commit mass killings at an individual level, the authors hope that the findings will prove useful in the prevention of future mass shootings. “The findings strongly suggest that focusing on mental illness, particularly psychotic illness, when talking about mass school shootings risks is missing other factors that contribute to the vast majority of cases, as well as exacerbating the already widespread stigma surrounding severe mental illness,” said study co-author Dr. Paul S. Appelbaum.

“To prevent future mass school shootings, we need to begin to focus on the cultural and social drivers of these types of events, such as the romanticization of guns and gun violence, rather than on individual predictors,” concluded Girgis.

Reference: Girgis RR, Rogers RT, Hesson H, Lieberman JA, Appelbaum PS, Brucato G. Mass murders involving firearms and other methods in school, college, and university settings: Findings from the Columbia Mass Murder Database. Journal of Forensic Sciences. doi: 10.1111/1556-4029.15161

This article is a rework of a press release issued by Columbia University. Material has been edited for length and content.