A suspect opened fire at the Abundant Life Christian School in Madison, Wis., on Monday, killing two people and injuring six more before dying of what police believe to be a self-inflicted gunshot wound.
It's one of more than 320 shootings that have taken place on school grounds this year alone, according to the K-12 School Shooting Database.
While school shootings are widespread in the U.S., this one is unusual because of the identity of the suspected perpetrator: Authorities have identified her as a 15-year-old girl.
Data shows that female shooters — at schools and in general — are relatively rare.
An FBI review of active-shooter incidents from 2000 to 2019 found that of the 345 total perpetrators, 332 were men and just 13 were women.
Similar statistics bear out when it comes to mass shootings, which the FBI defines as any incident in which at least four people are killed with a gun (so Monday's does not meet that criteria).
A staggering 97.7% of perpetrators of mass shootings from 1966 to 2019 were male, according to a Justice Department database.
The nonprofit Violence Prevention Project says that out of the 200 shooters involved in mass shootings between 1999 and 2024, only four identified as female and one as transgender — referring to the attacker in the 2023 shooting at a Christian elementary school in Nashville, Tennessee.
What makes female shooters rare — and different
Violence Prevention Project co-founder Jillian Peterson, a forensic psychologist and professor of criminology and criminal justice at Hamline University, says many school shooters "see themselves" in the perpetrators behind other tragedies — who have historically been men. Only nine female students have committed a school shooting since 1999, according to an analysis by the Washington Post.
"Many school shooters study Columbine, for example," Peterson told NPR in 2021. "Other university shooters study the Virginia Tech shooting. And they really are kind of using those previous shootings as a blueprint for their own."
More broadly, as NPR has reported over the years, experts say men are more likely than women to place blame on others (rather than on their own shortcomings), which could translate into anger and hostility.
And men tend to be more comfortable firing guns than women, who, studies show, are more likely to choose a knife if they do turn to violence.
Researchers Jason Silva and Margaret Schmuhl explored the demographics, motivations and incidents of female shooters between 1979 and 2019 for an article published in the Journal of Mass Violence Research in 2021.
They said existing studies attribute male mass shootings to "some form of male aggrieved entitlement or crisis of masculinity," often "motivated by grievances with women."
In contrast, they found that female mass shooters are not motivated by relationship disputes, often target workplaces and are more likely to work as part of a pair, "especially when engaging in ideologically motivated attacks."
"Just as women have exhibited distinct trends and patterns in homicide offending ... it is important for research to also distinguish and understand female mass shooters," they wrote.
Examples of female shooters in recent U.S. history
Shootings carried out by female suspects have dotted the headlines in recent years, particularly within the last decade.
In 2006, a former U.S. Postal Service employee fatally shot six people at a postal facility in Goleta, Calif., before taking her own life. Authorities said writings later found at the home of the woman, who had struggled with mental illness, indicated she believed she was threatened by a conspiracy involving postal employees.
In 2018, a woman with an apparent grudge against YouTube opened fire at the company's San Bruno, Calif., headquarters, wounding several people before fatally shooting herself.
That same year, a temporary employee fatally shot three people and then themself at a Rite Aid distribution center in Aberdeen, Maryland. While authorities and some friends initially identified the perpetrator as female, some media outlets later reported the shooter had started identifying as transgender in the years before the shooting.
Women were also part of pairs that carried out shootings, like the 2015 terrorist attack in San Bernardino, Calif., and the 2019 shooting at a kosher supermarket in Jersey City, N.J.
A teen girl was behind the 1979 school shooting that inspired a hit song
An infamous school shooting perpetrated by a girl happened in January 1979, when 16-year-old Brenda Spencer fired out of the window of her San Diego home at children arriving at the elementary school across the street.
Nine people, including children, were wounded, and two adults — the principal and janitor — were killed in the attack.
Steve Wiegand, a reporter with the San Diego Evening Tribune, began randomly calling homes near Grover Cleveland Elementary School to talk to potential eyewitnesses. He connected first with Spencer and, after talking for a while, got the sense the shots had come from her house. Wiegand asked why she did it.
"She said, 'Because I just don't like Mondays. Do you like Mondays? You know, it just livens up the day,'" he recalled.
On the other side of the country, Bob Geldof, the lead singer of the Irish new wave band Boomtown Rats, was being interviewed at a radio station in Atlanta when he saw a news story about the incident come across the wires.
Struck by Spencer's phrasing, he went back to his hotel room and penned "I Don't Like Mondays." The song, released in July 1979, spent four weeks at the top of the singles chart in the United Kingdom.
Spencer, meanwhile, was charged as an adult, pleaded guilty to two counts of murder and assault with a deadly weapon and was sentenced to life in prison.
She will be eligible for parole in 2025, and California Department of Corrections and Rehabilitation records show she has a hearing scheduled for February.
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