Media Play Up Faulty Study Suggesting Link Between Guns, Death Rates

Do fewer guns mean fewer firearm deaths? If you believe the March 6th issue of the Journal of the American Medical Association of Internal Medicine, the answer is "yes." A study by Eric Fleegler and four other co-authors received massive national news coverage from USA Today to the television networks. But the report is based on embarrassingly bad statistics that are rigged to get the result the authors wanted.

Take how they measure gun ownership. Believe it or not, this study measures gun ownership by looking at the share of suicides committed using firearms.

Then the authors go on to commit an egregious and basic statistical error. They claim that states with higher gun ownership have higher gun death rates. But wait a second -- most gun deaths are gun suicides. And what they call "gun ownership" in their study is also measured by gun suicides.

In other words, all the study proves is that more gun suicides leads to, well -- more gun suicides. Any serious statistical journal would not have published such nonsense.

The Fleegler study also involves a geographic comparison across the 50 US states of how the total number of gun laws is correlated with firearm deaths. (Quite glaringly, the authors exclude the District of Columbia, where gun laws are extremely strict and murders are much higher than any other state.) Unfortunately, they act as if they were totally oblivious to previous research in the area. Over almost two decades, three-dozen peer-reviewed studies by economists and criminologists have used a more massive data set and hundreds of factors that effect crime. The studies plowed through every single county in the US – a total of 3,140 – with data for each and every years for decades, starting with 1977. The most recent studies have analyzed over 80,000 observations.

There are good reasons to rely on 80,000+ observations rather than just 50. Even studying state changes year by year would have been vastly preferable. In particular, it allows for studying what happened before and after gun laws changed. Did laxer gun laws and more gun ownership lead to fewer murders? Or, did it make things worse?

But the Fleegler study does not even attempt to examine a single case of how deaths changed before-and-after gun ownership or laws changed.

This is extremely important and a quite common mistake also made by journalists. For instance, internationally, many will cherry pick a small set of countries. They will point to the UK and note that it has both a lower homicide and gun ownership rate than the US, implying that the lower gun ownership rate is responsible. But that isn't right. In fact, the UK had an even lower homicide rate before they had gun control regulations. Since the UK banned handguns in 1997, murder rates averaged 12 percent higher.

It is similar in the US. Fleegler et al. point to Massachusetts as having the nation’s most restrictive gun control laws and also enjoys a relatively low murder rate. In 2011, Massachusetts' murder rate was 59 percent of the national average, about 124 percent of its neighbors.

But just like with the UK, murder and violent crime rose after Massachusetts adopted its gun licensing rules in 1998. Since 1998, the number of registered gun owners in the state has plunged from 1.5 million to just over 200,000 today. And its murder rate soared from 70% of the average rate for its neighbors to 130%.

DC is yet another clear example. Since the Supreme Court struck down these laws in 2008, crime has plummeted. Few people have borne the costs to get handgun permits, but over 72,000 adults were suddenly able to use existing rifles and shotguns to legally defend themselves and their families. From 2008 to 2012, murder rates in DC have dropped by over 50 percent.

Fleegler et al could actually have gone a bit further with the meager data they studied. Instead of lumping together four years (2007 to 2010) to get an average for each state, they could have at least attempted to see if states that had the biggest changes in laws had bigger changes deaths. What would they have found? Well, I did this relatively simple exercise for murder and firearm murder rates for 2007 to 2011, finding that their measure of more gun laws implied more murders and no change in firearm murder rates.

There are numerous other problems with the study. But is it too much to ask medical researchers who venture into areas beyond their normal expertise to understand the existing literature? Or did the journal publish this shoddy work simply for political gain?

John R. Lott Jr. is a FOXNews.com contributor. An economist and former chief economist at the United States Sentencing Commission, he is also a leading expert on guns. He is the author of several books, including "More Guns, Less Crime." His latest book is "At the Brink: Will Obama Push Us Over the Edge? (Regnery Publishing 2013).". Follow him on Twitter@johnrlottjr.