Fact-checking Sen. Chris Murphy on the ages of mass shooters

Sen. Chris Murphy, D-Conn., has worked to enact restrictions on guns ever since the Sandy Hook school shooting in Newtown, Connecticut, an area he then-represented in the U.S. House of Representatives.

After another elementary school shooting — this one in Uvalde, Texas, on May 24, 2022 — Murphy gave an impassioned speech on the U.S. Senate floor to urge redoubled efforts to curb gun violence. The speech made the rounds of news shows and was widely shared on social media.

In an interview with CNN the day of the shooting, Murphy focused on the young age of the shooters in Uvalde and a May 14 mass shooting in Buffalo.

"I want to get rid of these assault weapons," Murphy said. "But maybe we can find common ground on just limiting who can get access to them, maybe say you have to be 21 instead of 18, seeing that most of these killers tend to be 18, 19 years old."

This fact-check will focus on whether "most of these killers tend to be 18, 19 years old."

When we checked with Murphy’s office, they pointed to a database project undertaken by The Washington Post that tracks every act of gunfire at a primary or secondary school during school hours since the Columbine High School massacre April 20, 1999. The Post found more than 200 incidents that met the project’s criteria.

When the Post analyzed these shootings, it found that more than two-thirds were committed by shooters younger than 18. The analysis found that the median age for school shooters was 16.

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Photo of a young man in a tie shows Wisconsin school shooter Natalie Rupnow.

So, using this criteria, Murphy is correct, even slightly understating the case.

For overall mass shootings — not just school shootings — academic studies have found that about a quarter of shooters were younger than 25.

A large-scale RAND study found that 26% of mass public shooters between 1976 and 2018 were younger than 25. Another study from the University of Alabama found that 27.2% were younger than 25, and that 6.8% were younger than 18.

A final point: Murphy referred to "killers," but the Post analysis he relied on included both incidents that resulted in deaths and those that did not.

Murphy said after the shooting in Uvalde that "most of these killers tend to be 18, 19 years old."

That’s largely accurate when looking at school shootings alone, according to a Washington Post database of school shootings since 1999. The database did include shootings that did not result in a death, and the share of teenagers committing mass shootings overall is smaller. 

We rate the statement Mostly True.

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