Author Stephen King once asked his publisher to pull one of his novels off the shelves.



Six people had died — in real life.



Four boys in 10 years brought guns to school. One killed a teacher and two students. Another shot five members of a prayer group, killing three. All four teenagers had read Rage, a book King wrote when he was a teen himself and published under another name.



King, in a blunt, impassioned essay, wrote that when he learned of the copycat crimes, he wanted the book off the market. He argues the United States should do the same for assault weapons.



"You don’t leave a can of gasoline where a boy with firebug tendencies can lay hands on it," he said in the 25-page piece, published Jan. 25, 2013, for Amazon Kindle readers.



King, a Democrat who says he owns three handguns and supports the Second Amendment, argues stricter gun control "would save thousands of lives." (His earnings from the sale of the essay will go the Brady Campaign to Prevent Gun Violence.) He says Australia shows it’s possible.



In 1996, 28-year-old Martin Bryant shot and killed 35 people near the Port Arthur historic site, a popular tourist destination. After the shootings, the country banned and bought up automatic and semi-automatic long guns, destroying at least 600,000 in 12 months — ultimately about a third of its privately owned guns.



It worked, King argues.



"Since the (Martin) Bryant killings and the resulting tough gun laws, homicides by firearm have declined almost 60 percent in Australia. The guns-for-everyone advocates hate that statistic, and dispute it, but as Bill Clinton likes to say, it's not opinion. It's arithmetic, honey."



He likes talking to "honey." He also drops a few F-bombs.



We wanted to know: Have homicides by firearm in Australia dropped almost 60 percent? And did those "tough gun laws" do it?



‘It’s arithmetic, honey’



We asked King and Australian and American experts in gun violence for evidence.



By a few different measures, the arithmetic works. Homicides by firearm did decline after 1996 — in fact, had already been in decline.



One path to "almost 60 percent" comes from statistics compiled in part by Philip Alpers, a public health professor at the University of Sydney. The number of gun homicides fell from 69 in 1996 (excluding the 35 victims of the mass shooting prompting the laws) to 30 in 2012.



That’s a decrease of 56.5 percent.



(And, yes, you read those numbers right — we didn’t miss any zeros. The United States has about the same number of gun homicides every day as happened in Australia last year.)



Then there’s King’s source, an item from Slate.com, he told us. It was a blog post citing a blog post citing a study — a reputable peer-reviewed piece in the American Law and Economics Review.



The researchers, Andrew Leigh of Australian National University and Christine Neill of Wilfrid Laurier University, found that in the decade after the gun laws, firearm homicides dropped 59 percent.



So, on the numbers, King has strong support.



But did the 1996 laws drive the numbers? That’s more vexing.



"He could be right. Or he could be wrong," said David Hemenway, director of the Harvard Injury Control Research Center who wrote a helpful 2011 summary of the evidence. " … The true answer is, we really don't know."



Leigh and Neill designed their study to test for the law’s effect. They asked whether death rates dropped more in states that destroyed relatively more banned weapons through gun buybacks.



They found the buyback program drove down firearm suicides by almost 80 percent, with no significant change in suicides that didn’t use guns. But the effect on homicides, while of "similar magnitude," was less precise, they wrote — perhaps between 35 and 50 percent.



Two other studies, which Hemenway described as flawed, found the laws made little difference. But their design made it nearly impossible to find an effect, he argues.



The first, authored by members of the Australian gun lobby, highlighted the fact that before the law passed, the firearm homicide rate was already dropping. If it had continued on that track, they found, that would explain the entire change — showing the law made no difference. The authors cherry-picked a high year for homicides to start their analysis, then assumed deaths would drop at the same linear rate forever — with negative deaths by 2015.



The second study was more sophisticated. Authors searched for a shift in deaths in a single year that might be attributed to the law, and found their tests suggested the law didn’t "have any large effects on reducing firearm homicide or suicide rates." Hemenway answers that the buyback occurred over two calendar years, in 1996 and 1997 — and the two-year drop was substantial. Gun homicides fell 46 percent.



Australian experts told us the science leans King’s way. But it’s not yet definitive.



"The truth is that gun homicide did decline substantially after the toughening of Australia's gun laws and the massive gun buyback," said Don Weatherburn, director of the New South Wales Bureau of Crime Statistics and Research. "The complication is that gun homicide was coming down before any of this. The academic debate is about whether the downward trend accelerated."



His own view? That there’s some evidence that tougher gun laws reduced the homicide rate, but it is "far from conclusive."



Paul Mazerolle, director of the Violence Research and Prevention Program at Griffith University in Brisbane, echoed that "more definitive work is required."



Some feel more certain the laws did their job.



Simon Chapman, a professor of public health at the University of Sydney, co-authored a 2006 study showing faster falls in firearm deaths after the laws.



"Six years on, there still has not been a massacre," he told PolitiFact.



But an even messier question is whether similar laws would work in the United States. Australia doesn’t have domestic gun manufacturers — and has the benefit of being, you know, an island. Guns destroyed aren’t so easily replaced.



Our ruling



King, urging his readers to support an American assault weapons ban, said that since Australia passed tough gun laws, "homicides by firearm have declined almost 60 percent." The raw numbers back him up — but cause and effect are much peskier questions. Scholars we spoke with say the evidence leans King’s way, but is less than conclusive. That’s an important clarification. We rate King’s claim Mostly True.