How Columbine became a blueprint for school shooters

When 12 students and one teacher were killed in Littleton, Colorado 20 years ago, it not only became what at the time was the worst high school shooting in U.S. history. It also marked when American society was first handed a script for a new form of violence in schools.

We make that observation as researchers – a psychologist and a sociologist – who have been studying mass public shootings as part of a grant from the U.S. Department of Justice.

Since the 1999 tragedy at Columbine High School, we identified six mass shootings and 40 active shooter incidents at elementary, middle or high schools in the United States. Mass shootings are defined by the FBI as an event in which four or more victims died by gunfire.

In 20 – or nearly half – of those 46 school shootings, the perpetrator purposely used Columbine as a model.

Columbine’s influence continues until this day. On April 17 – just three days ahead of the 20th anniversary of the Columbine shooting – authorities closed schools across Colorado due to a credible threat of a woman armed with a shotgun and who was “infatuated with Columbine.”

The ties that bind to Columbine

In our study of school shootings, we only looked at cases where a gun was fired on campus, following the practice of the Washington Post’s database on school shootings. Had we included foiled plots, the number would be significantly higher.

Several school shooters in our study were fascinated with Columbine and researched the massacre before their own. This includes the Parkland shooter, a 14-year-old who aspired to be “the youngest mass murderer,” and a 15-year-old who shot at his teacher after she refused to praise Marilyn Manson — the rock singer who was erroneously blamed for inspiring the Columbine killers.

The timing of the April 17 threat to Colorado schools is no coincidence. Prior perpetrators chose the anniversary of Columbine to commit their shootings, including one month and two years after. A different shooter talked of how he was going to “pull a Columbine.” Others discussed Columbine with classmates, even joked about it.

The Sandy Hook Elementary School shooter idolized the Columbine killers and curated a Tumblr account paying homage, alongside a graphic collage of Columbine victims. A North Carolina shooter was so obsessed with Columbine that he took a vacation there with his mother and fantasized about “finishing off” any wounded survivors.

Multiple shooters, including one 15-year-old in Oregon and another in Washington state, were inspired by a documentary about Columbine that included detailed recreations of what happened. One Wisconsin teenager held his classroom hostage after reading a book about Columbine.

Perpetrators also dressed in trenchcoats like the Columbine shooters, including those responsible for the 2018 Santa Fe shooting, where 10 people died, and a 2004 nonfatal shooting in New York. Indeed, the trenchcoat has appeared in subsequent school shootings because Columbine gave it meaning beyond any intrinsic use.