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Member Research & Reports

Member Research & Reports

BU: States with Permissive Gun Laws Have Higher Mass Shooting Rates

States with more permissive gun laws and greater gun ownership have higher rates of mass shootings than states with more gun control and fewer guns, and the divide is growing, according to a new study co-authored by Boston University School of Public Health (BUSPH) researchers.

The study, published in the British Medical Journal, found that each 10-unit increase in state permissiveness was associated with an 11 percent higher mass shooting rate, and a 10-percent-higher state firearm ownership rate was associated with a 35 percent higher rate of mass shootings.

“Permissive gun laws and increased gun ownership have had a big role in increasing the number of mass shootings that we experience in this nation,” says study co-author Dr. Bindu Kalesan, assistant professor of community health sciences at BUSPH. “Permissive gun laws have no place in civilized societies, and we need educational programs for reducing gun ownership.”

The researchers used the 1998 through 2015 editions of the Traveler’s Guide to the Firearms Laws of the Fifty States to create a restrictiveness – permissiveness scale of U.S. state gun laws, including carry and permit requirements, semiautomatic guns and high capacity magazines, vehicle gun possession, carrying guns where alcohol is served, and out-of-state permit recognition, among others. Each state received a ranking for each year from 1998 to 2014, with a rating of zero (0) meaning the state’s gun laws were completely restrictive, and 100 meaning completely permissive.