Fernanda Crescente

USA TODAY

WASHINGTON — Major gun law reforms in Australia enacted 20 years ago have eliminated fatal mass shootings there, according to a study published Wednesday in the Journal of the American Medical Association.

Before Australia enacted the reform, it had 13 mass shootings in the span of 17 years.

The study, conducted by three Australian university researchers, was released two days after the Senate rejected four measures that would increased background checks for potential gun buyers and stopped people on the terror watch list from buying guns.

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Authors Simon Chapman and Philip Alpers from the University of Sydney, and Michael Jones from Macquarie University sought to determine whether the enactment of gun law reforms and buyback programs had an impact on the number of mass firearm homicides and total firearm deaths in Australia.

Australia's National Firearms Agreement was passed shortly after a mass shooter used an assault rifle to kill 35 people and wound 19 others in Tasmania in 1996. Lawmakers in the conservative-leaning government of Prime Minister John Howard then banned rapid-fire long guns and created a buy-back program to get more guns off the street.

By the following year, Australia had implemented strict criminal penalties to all in possession of prohibited weapons, including imprisonment and fines.

The agreement also required Australians who wanted to own guns to document a “genuine need” to have them, have no convictions for violent crimes within the last five years or restraining orders for violence, demonstrate good moral character, pass a gun safety test and register their firearms.

“It is difficult to pinpoint precisely which aspect of the policy contributed to this success,” said corresponding author Daniel Webster in an editorial for JAMA. “But the substantial reduction in the population’s exposure to semiautomatic long guns capable of large-capacity magazines for ammunition is likely to have been key.”

However, the authors did not establish a direct correlation between gun law reforms and a decline in firearm deaths, since the total number of non-firearm suicides and homicides also decreased in Australia.

Two of the three authors — Chapman and Alpers — have previously been members of a gun-control groups, while Webster is chairman of a program at Johns Hopkins University in Baltimore that is supported by a foundation led by former New York mayor Michael Bloomberg, a vigorous supporter of gun control.

“Political, cultural and legal challenges make it highly unlikely that the United States would implement comparable policies,” Webster wrote. “Yet the experience in Australia over the past two decades since enactment of the NFA provides a useful example of how a nation can come together to forge life-saving policies despite political and cultural divides.”