Gun-control advocates in the U.S. often point to Australia as proof that Americans would be safer with a ban on semiautomatic weapons. In the land down under, there has been a total of zero mass shootings since rapid-fire guns were outlawed in the 1990s.
But a new analysis of crime in Australia stops short of giving gun-control laws the credit for this remarkable run. The reason: Although homicides involving guns have declined over the past 20 years, homicides committed without firearms have dropped even more.
"Because of this, it is not possible to determine whether the change in firearm deaths can be attributed to gun law reforms," researchers concluded in a study published Wednesday in the Journal of the American Medical Assn.
The centerpiece of the NFA is a set of strict prohibitions on rapid-fire rifles and shotguns. Other parts of the agreement require gun buyers to demonstrate a "genuine need" for a weapon, pass a gun safety test, wait at least 28 days for the purchase to go through and then register their firearm, among many other conditions. The Australian government also sponsored two gun buyback programs that resulted in the destruction of at least 728,667 weapons.
A trio of researchers wanted to know whether those efforts succeeded in reducing firearms-related deaths in the country — and if so, whether the reduction in shootings was offset by additional homicides committed by other means.
The researchers, from the University of Sydney's School of Public Health and the psychology department at Macquarie University in Sydney, analyzed information from Australia's National Injury Surveillance Unit. The data included information on all deadly shootings in the country, with the exception of justified shootings by police.
In the 17 years before the Port Arthur massacre, there were 12 other mass shootings in Australia that left at least five people dead, not including the the shooter. Altogether, 104 victims died in these 13 events, along with eight of the shooters.
All of those figures have dropped to zero in the 20 years since Port Arthur.
But that's not enough to make a strong case for gun control. So the researchers examined other trends before and after the strict laws went into effect.
Each year between 1979 and 1996, Australia had an average of 3.6 gun deaths (both homicides and suicides) per 100,000 people. After the NFA was passed, that rate dropped to an average of 1.2 gun deaths per 100,000 people.
In both time periods, the total number of firearm-related deaths was on the decline. But "the trend accelerated" after gun control took effect, the researchers wrote.
The researchers also found that passage of the NFA was associated with a steep drop in the overall homicide rate. Before Port Arthur, homicides involving weapons of any kind had been falling at a rate of 0.3% per year, on average. Afterward, they fell by 3.1% per year. There was no evidence that killers who couldn't get their hands on guns switched to other weapons instead, the team wrote.
In addition, the suicide rate — which had been rising by an average of 1% per year — fell by 1.5% per year after the country's gun laws changed. Without guns available to them, suicidal people were simply less successful in their attempts to end their lives, the researchers speculated.
Overall, gun-related deaths fell faster after gun control than before it. But some of those gains might be due to factors that have nothing to do with guns. For instance, trauma doctors and surgeons have gotten better at treating gunshot victims. They're also getting treated more rapidly in the NFA era, thanks in part to the growing ubiquity of cellphones, the researchers wrote.
Put it all together and the researchers couldn't say with certainty that Australia's stricter gun laws were responsible for the drop in gun-related deaths.
Indeed, connecting those dots was a tall order, according to Daniel Webster, director of the Center for Gun Policy and Research at the Johns Hopkins Bloomberg School of Public Health. Since all of Australia's states and territories adopted the NFA, there's no clear way to gauge what would have happened in the absence of the agreement.
Still, the study offers "convincing evidence that the new policies enacted in 1996 appear to have helped prevent future mass shootings," Webster wrote in an editorial that also appears in JAMA. "A reasonable interpretation of the data … is that Australia's restrictions on guns enacted in 1996 likely spared the country from a significant number of fatal mass shootings."
Webster called on Americans to take a cue from Australians and demand that their elected representatives "adopt measures to prevent the loss of life and terror of gun violence."
Last week, the American Medical Assn. declared gun violence a "public health crisis" in the U.S. and vowed to lobby Congress to clear the way for the Centers for Disease Control and Prevention to conduct research on gun violence.
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