Mass shootings are horrific, and their impact is devastating. But far from dissuading people from purchasing guns, mass shootings can cause gun sales to soar as people race to buy protective weapons they fear could be banned in the future.
The trend is worrisome. And now, new research suggests the increased availability of firearms in the aftermath of a mass shooting can also cause an increase in gun-related deaths.
And the worst part? Children are especially at risk.
To conduct this important study, the researchers looked at the five-month period following the mass shooting at Sandy Hook Elementary School, which claimed the lives of 20 schoolchildren and six adult members.
They found exactly what the trends predict: an increase in guns sold in the aftermath of the shooting. In fact, the study reveals 3 million additional guns were sold following Sandy Hook.
Beyond the number of accidental gun deaths that would be expected with more guns, the researchers estimated 57 to 66 additional gun deaths occurred after Sandy Hook. And 17 to 22 of those cases took the life of a child.
These results do not stand on their own - they are merely the latest in a series of studies that have been examining the public health impact of firearms. The study is buttressed by a whole score of previous research, which has found strong links between increased gun ownership and firearm-related injuries and deaths. Previous studies have also found consistently higher rates of firearm deaths among those living in households with ready access to guns.
In October, a new study revealed in the weeks following gun shows in Las Vegas, gun deaths and injuries rose by 70 percent in nearby California. Plus, a study published earlier this year found a 53 percent boost in gun sales in California in the six weeks following Sandy Hook.
"This is part of this blossoming in gun research," said Duke University emeritus professor Philip J. Cook, a pioneer in the field of firearms injury research who wasn't involved in the new study.
The link the recent study has drawn between increased gun sales and accidental shootings is by no means conclusive. But there are several aspects of the research that strongly suggest the behaviour of gun buyers influenced the rise in accidental gun deaths after Sandy Hook.
The authors, who were health economists from Wellesley College and the National Bureau of Economic Research, used several measures to gauge the increase in "gun exposure" after Sandy Hook.
For instance, they predicted presumptive gun sales by analysing the spike in background checks required for most sales. They also counted the number of Google searches about buying and cleaning guns. In the latter analysis, the authors found evidence to suggest gun owners were bringing old guns out of storage after Sandy Hook.
In other words, both established and prospective gun owners were preparing to increase the number of firearms in their home, following a mass shooting.
By searching through a federal database of recorded deaths, the researchers found "evidence of a spike in accidental firearm deaths to children exactly at the time of the increase in gun sales after Sandy Hook."
And this spike is by no means a random fluke. Try as they might, the researchers could find no similar increase in any of the other time periods they looked at.
Even their statistical projections, which looked at the relationship between the number of guns in the U.S. and fatal gun accidents, were a near-perfect match to reality.
But the most important piece of data is this: when the researchers mapped the increase in accidental gun deaths, they found they were concentrated in places where the post-Sandy Hook spike in gun sales was very high.
"This is the pattern we would expect to see if those who purchase guns (and perhaps those who remove guns from storage) are more likely to succumb to accidents until those guns are stored in a safer environment," wrote the authors, Phillip B. Levine and Robin McKnight.
Stephen Teret, who directs Johns Hopkins University's Center for Law and the Public's Health and was not involved in the study, called the new research "a methodological tour de force."
But Teret says there is still not enough data to suggest educating people on safe gun storage is effective in reducing firearm injuries.
"And there are better ways to reduce gun deaths than to tell people to be more careful. Those include changing the design of these guns so kids can't operate them," said Teret.
These are complicated issues, and figuring out how to solve them is not easy. But when enough scientific evidence is gathered, it can help point legislators in the right direction. If the U.S. wants to save lives from gun-related violence, we need more scientific research, and not less.