Here’s why guns increase the risk of suicide–especially in stressful times

Handguns for sale are lined up in a display case at Frontier Justice in Lee’s Summit, Mo on , Dec. 21, 2108. AP Photo Charlie Riedel

People who own a handgun are almost four times more likely to die by suicide than those who don’t have guns, according to new research by Matt Miller, a professor of health sciences and epidemiology at Northeastern.

The findings, published by Miller’s group in The New England Journal of Medicine, come at a time when mental health professionals are bracing for a potential surge in suicides based on social and financial pressures borne of the COVID-19 pandemic.

Matthew Miller, a professor of health sciences and epidemiology in the Bouvé College of Health Sciences, has been researching injury and violence prevention for two decades. Photo by Matthew Modoono/Northeastern University

“It reinforces what we in some ways already knew,” Miller says of the handguns study. “Which is that if someone is going through a hard time, the single most effective thing you can do to reduce the likelihood that that person is going to die is to get that gun out of the home, or otherwise make it inaccessible to the person who’s at risk.”

Limiting access to guns is crucial to mitigating deaths by suicide because, as the study notes, suicide attempts are “often impulsive acts, driven by transient life crises.” Miller says that when attempts are made with pills or by cutting—the most common methods—a fatal outcome is much less likely than if a gun had been used. 

Among suicide survivors in general, he says, fewer than 10 percent will go on to die in a subsequent attempt. Such reprieves are rare for people who attempt suicide with a gun.

“The vast majority of people who attempt suicide with a gun don’t get a second chance,” Miller says.

In a recent opinion column in the New York Times, Miller and his co-authors dispelled the myth that “people who really want to end their lives will find a way to do it.” Miller’s two decades of public health research have shown him that gun owners are not more suicidal than people who live in homes with no guns, but they are more likely to die by suicide because when they make an attempt they are far more likely to use a gun.

“This underscores the fact that we as a society need to recognize the risk of suicide and do something about it, in the way that we have done something about drunk driving fatalities,” says Miller, who was senior author of the study. “When you’re drunk, I’m going to take away your car keys. Similarly, when people are going through hard times and there are guns in that home, it should be a no-brainer to remove those guns from the home and make them inaccessible as a way to save lives.”

The study found that 14 percent of the victims killed themselves in the first month of handgun ownership, which suggests that a small minority of people bought guns with the intent of suicide. But more than 85 percent of the suicide deaths happened months or years after the initial handgun purchase.

The study was able to break new ground because it relied on data from the state of California, where handguns are registered. It followed 26 million adults in California over a 12-year period, making it the first study to track gun owners from the day they purchased their first handgun.

“California has, in effect, a gun registry: They know who owns guns, when they acquire guns, and when they get rid of guns,” Miller says. “It would advance gun research greatly if other states had a similar record of gun transfers, in the way that we know whether somebody owns two cars or three cars. That makes California the go-to place for this kind of gun research.”

Miller says that he and his co-authors from Stanford, the University of California-Davis, the Erasmus Medical Center (Netherlands), and the University of Melbourne (Australia) are planning to collaborate on a variety of other California-based studies, including a deep look at the risk that a handgun imposes on children and other household members who are not the registered owner. 

For media inquiries, please contact Shannon Nargi at s.nargi@northeastern.edu or 617-373-5718.