Mass School Shootings Are Not Caused by Mental Illness

Summary: Most perpetrators of mass school shootings do not suffer from severe mental illness, a new study reports. When psychosis is present, mass murderers in an academic setting use means other than firearms to commit their crimes. Consistent with previous findings, the majority of mass school shooters are male and caucasian, and almost half of school shooting episodes end with the perpetrator’s suicide.

Source: Columbia University

A research team at Columbia University Irving Medical Center and the New York State Psychiatric Institute (NYSPI) examining 82 mass murders that occurred at least partially in academic settings throughout the world, found that most mass murderers and mass shooters did not have severe mental illness.

The study, led by Ragy R. Girgis, MD, and Gary Brucato, PhD, associate research scientist, also found that most mass murderers used firearms, and semi- or fully-automatic firearms most commonly. Among incidents of mass school murder not involving firearms, stabbing was the most common method.

The research, published online Oct. 27, in the Journal of Forensic Sciences, according to study authors, is largest analysis ever conducted on mass school shootings.

“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. Girgis, director of the Center of Prevention and Evaluation (COPE), a research clinic at Columbia/NYSPI specializing in the study and treatment of young adults at high risk for schizophrenia and other psychoses.

“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.”

To conduct their study, the researchers analyzed data from the Columbia Mass Murder Database (CMMD), developed by the COPE team to gain much-needed insight into the relationship between serious mental illness and mass shootings. Creating the CMMD involved extensive review of 14,785 murders publicly described in English in print or online, occurring worldwide between 1900 and 2019.

For the mass school shooting study, the researchers isolated cases of mass murder perpetrated at least in part at schools, colleges, and universities and categorized them by location (within or outside of the US), and whether firearms were used.

Of the 82 incidents of mass murder involving academic settings:

–  Nearly half (47.6%) and most involving firearms (63.2%) were U.S.-based 

– Consistent with previous reports, perpetrators of mass shootings involving academic settings are primarily Caucasian (66.7%) and male (100%)

– Severe mental illness (e.g., psychosis) was absent in the majority of perpetrators; when present, psychotic symptoms are more associated with mass murders in academic settings involving means other than firearms

– About half (45.6%) of mass school shootings ended with the perpetrator’s suicide

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Severe mental illness (e.g., psychosis) was absent in the majority of perpetrators; when present, psychotic symptoms are more associated with mass murders in academic settings involving means other than firearms. Image is in the public domain

Coauthor Paul S. Appelbaum, MD, the Elizabeth K. Dollard Professor of Psychiatry, Medicine and Law at Columbia, said that identifying mental illness as a primary cause of violence is misleading. 

“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 Dr. Appelbaum.

Noting that almost half of mass shooters took their own lives at the scene, the authors hypothesize that perpetrators may see themselves as engaging in some form of final act.

The researchers hope that the findings will help lawmakers and law enforcement officials better understand the phenomenon of mass school shootings, as well as how mass school shootings differ from other forms of mass murder. The authors also emphasize that these data cannot be used to predict behavior on an individual level.  

About this mental health and mass shooting research news

Author: Carla Cantor
Source: Columbia University
Contact: Carla Cantor – Columbia University
Image: The image is in the public domain

Original Research: Closed access.
Mass murders involving firearms and other methods in school, college, and university settings: Findings from the Columbia Mass Murder Database” by Ragy R. Girgis et al. Journal of Forensic Sciences


Abstract

Mass murders involving firearms and other methods in school, college, and university settings: Findings from the Columbia Mass Murder Database

While mass murders involving academic settings, especially using firearms, are of grave, growing public concern, identifying consistent patterns to aid prevention has proved challenging.

Although some characteristics, such as male sex, have been routinely associated with these events, another hypothesized risk factor, severe mental illness, has been less reliably predictive.

We isolated cases of mass murder perpetrated at least in part at schools, colleges, and universities from the Columbia Mass Murder Database (CMDD) and categorized them by location (within or outside of the US), and whether firearms were used. Demographic similarities and differences between groups were analyzed statistically wherever possible.

We examined 82 incidents of mass murder, by any means, involving academic settings. Nearly half of all incidents (47.6%), and most involving firearms (63.2%), were U.S.-based, whereas those not involving firearms largely occurred elsewhere (88.0%).

Consistent with previous reports, perpetrators of mass shootings involving academic settings are primarily Caucasian (66.7%) and male (100%). Severe mental illness (i.e., psychosis) was absent in the majority of perpetrators (firearms: 80.7%; nonfirearms: 68.0%). About half (45.6%) of mass school shootings ended with the perpetrator’s suicide.

When present, psychotic symptoms are more associated with mass murders in academic settings involving means other than firearms.

The question of whether perpetrators of such incidents may perceive their actions as a kind of final act might enhance policy development and/or how law enforcement intervenes.

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  1. I think mass killers have decided to they are going to commit suicide, for whatever reason.
    They feel they are unimportant in society but want to make a point of being in the history books of crime. Killing children has the most impact.I think the media should not mention their names and therefore deprive them of post glory and attention they seek. (I’ll show them, I was important)It would have been interesting to known what percentage of them went to that particular school where they killed the children.

  2. Wow, at all of the negative comments on the only study to date that is actually getting closer to the answer! That says a lot! I would tell you who is doing this and how, but they are already trying to kill me for speaking out on other “top secret/classified” issues. However, I will say the author of the study is definitely onto something, specifically what role law enforcement plays, and how they see this as a final act. Specifically, they can not take it any longer! The US govt has a long history of non-consensual human experimentation. I won’t say anything else, as I don’t want to be one of the mind controlled/driven to insanity murderers, who are told this is the way to end the torture!

  3. Where to start?… Set your face to Stunned while I summarize.
    If you have ever asked yourself exactly where and how an educational institution pisses away so much money, look no further. You have struck gold.
    1: Mass Murder (MM) is Three or more people. Leaving the number of victims out for each case is a scare tactic, and just one of many reasons this study is biased, a piss poor political hit piece aimed at subverting Constitutionly protected inalienable rights and complete Garbage.
    2:”Nearly Half” actually means “Less than half”. Less than half of MMs involving a Gun occurred in the USA. Less than half perpetrators committed suicide, ect.
    3: In the USA, most academic MMs committed by Caucasian males. This is consistent with the population.
    USA population, Caucasian – 60%
    4: Access to firearms in countries outside of the USA, NO DATA.
    The list goes on and on. Were my R&D team to present a study done this poorly, I would pink slip every one of them. This entire study was a complete waste of time, money, & resources. It is intentionaly misleading and has purposefully omitted many factors that are necessary for a complete and thorough study.
    Absolute garbage! And a complete waste of what could have been a great study.

    TWO THUMBS DOWN!
    ZERO OUT OF FIVE STARS!

  4. imo if 47% are killing themselves they defiantly have some type of mental illness. bullying has gotten worse. dont underestimate the bully. i felt like i was close to being one of those kids when i was in school cus i was so angry at a few ppl and if a few ppl got in my way so be it. i got help tho.

    1. Are you referring to the actual study, or to the report that’s on this page? The actual study is in a peer-reviewed journal. You can’t really fault the University if the writers of this article weren’t as specific in their reporting as you would like.

  5. What a misleading title. Mental illness isn’t defined by psychosis. Psychosis is a form of mental illness. Just because the average school shooter isn’t having a psychotic episode, doesn’t mean they aren’t mentally ill. The act they’re perpetrating isn’t an act a mentally well person would do. Back to my original point, the title seems to be purposefully misleading to entice people into reading this dumb article.

  6. So what you’re really saying is they are not clinically insane…they ARE mentally ill by defenition of the act. This is probably one of the dumbest consclusions, or spins on a study that I’ve ever seen.

  7. I say look into video games, isolation and low esteem. Guns are not the issue here. Did we have this problem in the 40’s,50’s and 60’s. So what has changed? Hollywood producers using violence in every movie and not just with guns. Poor parenting, drugs and alcohol no restrictions. Social media has destroyed the human race along with COVID. School shootings would be prevented if the Feds would make it mandatory that all schools have metal detectors at the entrance and doors are locked electronically. But they would prefer two more football fields and another soccer field instead.

  8. Sometime ago the author Richard Rhodes wrote about a criminologist who had successfully identified the steps/characteristics that predicted cold-blooded killers- those who even out of prison, would predictably kill again (& thus identifying those who need either life terms, or extreme monitoring), through a step-wise process called violentization.

    The book is called “Why they Kill”, by Richard Rhodes, about Criminologist Lonnie Athens.
    Well worth reading.
    We need a Lonnie Athens to study these mass murderers in the same fashion.

  9. How much did the authors pocket from NRA to call this blatantly misleading and wrongful article/ title. These statistics are not a good depiction of reality. If not mental illness what is the cause for school shootings you ask? RECKLESS LOBBYING, NRA, and gun sale with no oversight of a gun ownership/ license.

    Sad and upset by these news articles stooping low and publishing CRAP for the sake of $. At what cost? Cost of innocent kids’ lives

    1. You hit the nail on the head. Specifically, the Intel agencies. They have a long history of killing people for political purposes, ie.JFK

  10. Would love to know the percentage of cases where psychosis is present. Also omitted from the study – or this article, what percentage of the cases involved the assailant taking anti-depressants or other types of drugs.

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