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What makes the San Bernardino shooting so unusual

Mass shootings are almost never perpetrated by women, or by couples.

Law enforcement officials are still trying to figure out why Syed Farook and Tashfeen Malik went on a shooting rampage Wednesday at a San Bernardino social services center, killing 14 people. But what’s already clear is how unusual the crime was for two reasons: It involved two shooters, and one of them was a woman.

California Sen. Dianne Feinstein told reporters she found it hard to believe. “You and I know, that women, we wouldn’t leave a six month old -- our baby -- to do this, to don tactical gear to go in and kill a bunch of people,” she said.  “It’s not something a woman would easily do. So it’s going to be very interesting for me to see what her background was, what level of animus she had, because she had to have had a considerable level." Feinstein added of the fact that Malik and Farook left behind their six-month old child. “A woman is a woman. And her child has to be of maximum importance to her.”

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Of the 160 mass killings the FBI defined as “active shooter incidents” between 2000 and 2013, only two of them had more than one shooter. Only six, or 3.8%, involved a woman pulling the trigger.

It is also highly unusual for a couple to engage in a mass killing spree together. The closest comparison in the United States was in 2014, in an incident that happened after the FBI’s cutoff for its study. That June, a young married couple, Jerad and Amanda Miller, ambushed and killed three victims, including two police officers. (Jerad, 31, died in the shootout, and Amanda, 22, killed herself on the spot.)

Not only are most mass shooters male, but in about 10% of the active shooter incidents measured by the FBI, the perpetrators targeted women in their lives, including “current, estranged, or former wives as well as current or former girlfriends.”

Overall gun fatalities paint an even starker picture. “If you look at gun violence, women are far more likely to be the victims,” said Jonathan Metzl, the director of the Center for Medicine, Health, and Society at Vanderbilt University, who studies gun violence.

Farook and Malik were reportedly married for two years, after Farook went to Saudi Arabia to meet the Pakistani-born Malik. While authorities haven’t confirmed a link to international terror groups, Metzl raised the possibility that one half of the couple may have radicalized the other, or transmitted delusions, which psychiatrists refer to as “folie à deux.”

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Malik may not be the last female mass shooter to wreak havoc in the United States.

“Mass shootings are by definition copycat crimes,” Metzl said. “So it’s not surprising even though there’s one demographic that is frequently associated with mass shooting, other demographic groups would copy that form.” He added, “As guns in this country increasingly become modes of conflict resolution, I think that we’re going to see a lot more diversity in the mass shooter pool.”  

Mary Ellen O’Toole, director of the Forensic Science Program at George Mason University and editor-in-chief of Violence and Gender, agreed. “Shootings involving mission-oriented females may be a new threshold which should be concerning to all of us," she wrote in a statement to reporters, "and the incident in San Bernardino might just be a hybrid, and a harbinger, of shootings to come."