Tread lightly, Americans: Nearly 9% of people in the United States have outbursts of anger, break or smash things, or get into physical fights -- and have access to a firearm, a new study says. What’s more, 1.5% of people who have these anger issues carry their guns outside the home.

The findings, published Wednesday in the journal Behavioral Sciences and the Law, suggest that measures to reduce gun injuries and deaths should focus less on diagnosed mental illness and more on a history of violent behavior.

The new research also indicates that the 310 million firearms estimated to be in private hands in the United States are disproportionately owned by people who are prone to angry, impulsive behavior and have a potentially dangerous habit of keeping their guns close at hand. That’s because people owning six or more guns were more likely to fall into both of these categories than people who owned a single gun.

In 2012, 11,622 people in the United States were killed by a firearm discharged during an intentional act of violence, and an additional 57,077 were injured. Although mass shootings have focused lawmakers’ attention on the need to keep guns out of the hands of those with a serious mental illness, the new study implies that doing so would make only a small dent in this tally of morbidity and mortality.


Researchers from Duke, Harvard and Columbia Universities analyzed data gleaned from 5,563 face-to-face interviews conducted as part of a nationwide survey of mental disorders back in the early 2000s. The study authors say they are the first to estimate the overlap between gun access and a history of angry, impulsive behavior -- with or without a diagnosable mental illness.

Fewer than one in 10 of those angry people with access to guns had ever been admitted to a hospital for a psychiatric or substance abuse problem, the study found.

Their behavioral history might suggest a propensity for violence, according to the study. But nothing in their medical histories would bar them from legally purchasing guns under existing mental health related restrictions.

“Gun violence and serious mental illness are two very important but distinct public health issues that intersect only at their edges,” said study leader Jeffrey Swanson, a professor of psychiatry and behavioral sciences at Duke University School of Medicine.


“The traditional legal approach has been to prohibit firearms from involuntarily committed psychiatric patients,” Swanson added. “But now we have more evidence that current laws don’t necessarily keep firearms out of the hands of a lot of potentially dangerous individuals.”

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