Australia and the United States share many characteristics. Both are English-speaking democracies of multicultural immigrants. The 2 nations have been allies for nearly a century. Australians and Americans consume similar diets of movies, video games, popular music, recreational drugs, and alcohol. Both have vast interiors, early histories of armed European settlers mistreating native populations, plenty of feral pests to shoot, and many firearm enthusiasts. Yet the 2 countries differ dramatically on the issue of gun violence. The U.S. population is 13.7 times larger than that of Australia, but it has 134 times the number of total firearm-related deaths (31 672 vs. 236 in 2010) and 27 times the rate of firearm homicide (11 078 [3.6 per 100 000] vs. 30 [0.13 per 100 000] in 2010) (1).

The event that spurred this change in Australian gun control occurred on 28 April 1996 at the tourist site of Port Arthur, Tasmania, when a gunman killed 20 people in 90 seconds with his first 29 bullets. This “pathetic social misfit” (the judge's words) was empowered to achieve his final toll of 35 people dead and 18 seriously wounded by firing semiautomatic rifles originally advertised by the gun trade as “assault weapons.” Like most mass shooters in Australia and New Zealand, the killer had neither a criminal record nor a diagnosed mental illness.

In the 12 days after this event, Australia's 6 states, 2 territories, federal government, and opposition parties agreed to enact a comprehensive suite of firearm law reforms (2). John Howard, the newly elected and conservative prime minister, quickly reformed gun control laws. Since then, there have been no mass shootings and an accelerated decline in total gun-related deaths (3). All sides of Australian politics view tighter gun laws as a triumph of Howard's administration.

Key components of the reforms included a ban on civilian ownership of semiautomatic long guns and pump-action shotguns; a market-price gun buyback program financed by a small, one-off income tax levy on all workers; proof of genuine reason for firearm possession; the formal repudiation of self-defense as a legally acknowledged reason to own a gun; prohibition of mail or Internet gun sales; and required registration of all firearms (2). In a long series of state and federal gun amnesties and guns being voluntary surrendered for destruction, Australians have smelted more than 1 million firearms, or one third of the national civilian arsenal. An equal number in the United States would be 90 million guns (3).

On the day of the massacre in Sandy Hook, Connecticut, one of us tweeted a link to our report on gun deaths in Australia during the decade after the Port Arthur massacre and ensuing reforms (4). In the 6 years since our paper was published, readers accessed it online 14 742 times. During December 2012, a total of 82 310 people accessed it (see http://injuryprevention.bmj.com/articleusage?rid=12/6/365). Demand led to the reprinting of a book detailing the events surrounding Australian gun control (5), which was also made available as a free download. The world, particularly Americans, seems thirsty for information about the Australian experience.

The U.S. gun lobby argues that, because people (not guns) kill people, gun control will not reduce gun deaths. The Australian experience can inform this debate.

Whereas firearm suicides and single-victim homicides, such as domestic murders and criminal-on-criminal shootings, dominate the landscape of firearm-related deaths in industrialized nations, it was a mass shooting that outraged Australians and oxygenated public demand for gun control. The firearms banned from civilian ownership in Australia are frighteningly efficient, mass-killing machines originally designed for military combat. These weapons contribute little to target shooting or hunting. At the time, and across all mainstream media, gun lobby pleas to allow open civilian access to weapons designed for the battlefield were labeled as “un-Australian” extremism (5). Prime Minister Howard stated that “This country, through its governments, has decided not to go down the American path in regard to guns.” But few predicted that a ban on semiautomatic weapons to prevent massacres would have had a significant impact on Australia's total gun deaths. Then, as now, unintentional shootings and suicides were responsible for 75% to 80% of gun deaths. Yet, the ban on semiautomatic weapons led not only to a 16-year absence of gun massacres but also an accelerating decrease in the total rates of gun deaths (3).

The rate of firearm homicide, which was decreasing by 3% per year before the reforms, decreased 7.5% per year after the new laws. This change failed to reach statistical significance (P = 0.15) because of the relatively small numbers involved, but it remains notable (4). Firearm-related suicides in Australian men declined from 3.4 to 1.3 per 100 000 person-years (a 59.9% decline) between 1997 and 2005, while the rate of all other suicides declined from 19.9 to 15.0 per 100 000 person-years (a 24.5% decline), suggesting no substitution effect (6). The yearly change in firearm-related suicides in men was −8.7% per 100 000 person-years (95% CI, −10.2% to −7.0%), and the yearly change in other suicides was −4.1% (CI, −4.7% to −3.5%), less than half the rate of decrease in firearm suicide (6). Although gun lobby researchers in Australia have sought to repudiate these data (7) using methods that have been heavily criticized (8, 9), to date no peer-reviewed research has established a plausible alternative cause for these accelerated declines. Meanwhile, others have attributed even stronger public safety effects to Australia's firearm reforms (10).

A nation's incidence of firearm deaths reflects many cultural, economic, and legislative factors. Those implacably opposed to Australia's reforms remain intent on attributing the declining incidence of gun death to anything but the new gun laws and the destruction of one third of the nation's firearms. But Australia's public health initiatives resemble the explanatory elephant in the room. No factor other than the dramatic reduction in access to the semiautomatic weapons needed by those planning massacres has been advanced to plausibly explain the cessation of mass shootings in Australia.

Although pro-gun spokespersons remain obsessed with the injustice of “decent law-abiding shooters” being “treated like potential criminals,” this rhetoric finds little traction in Australia, where drivers are regularly treated as potential public menaces at random breath-testing checkpoints and travelers as possible terrorists when passing through airport security.

Recently, a public health approach to gun control has taken root in the White House. Each of President Obama's recommendations has its basis in evidence-based public safety interventions patiently researched by our U.S. colleagues. Interventions similar in intent and design to those that successfully reduced the toll of guns on the lives of Australians may, perhaps, take hold in the United States.

References 1. Alpers P, Wilson M, Rossetti A. Guns in Australia: facts, figures and firearm law—Death and Injury, Total Gun Deaths and Gun Homicides compared to the United States. Sydney, Australia: Sydney School of Public Health, The University of Sydney; 2013. Accessed at Google Scholar Guns in Australia: facts, figures and firearm law—Death and Injury, Total Gun Deaths and Gun Homicides compared to the United States. Sydney, Australia: Sydney School of Public Health, The University of Sydney; 2013. Accessed at www.gunpolicy.org/firearms/compare/10/total_number_of_gun_deaths/65,66,69,87,136,177,192,194 on 28 February 2013.

2. Commonwealth of Australia. Resolutions from a special firearms meeting. Canberra, Australia: Australian Police Ministers Council; 10 May 1996. Google Scholar Resolutions from a special firearms meeting. Canberra, Australia: Australian Police Ministers Council; 10 May 1996.

3. Alpers P. The big melt: how one democracy changed after scrapping a third of its firearms. In: Reducing Gun Violence in America: Informing Policy with Evidence and Analysis. Webster DW, Vernick JS, eds. Baltimore: Johns Hopkins Univ Pr; 2013:205-11. Accessed at Google Scholar The big melt: how one democracy changed after scrapping a third of its firearms. In: Reducing Gun Violence in America: Informing Policy with Evidence and Analysis. Webster DW, Vernick JS, eds. Baltimore: Johns Hopkins Univ Pr; 2013:205-11. Accessed at http://jhupress.files.wordpress.com/2013/01/1421411113_updf.pdf on 11 February 2013.

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