A collection of classroom-safe training pistols from a concealed-weapons permit class in Florida. (BRIAN BLANCO/REUTERS)

“The facts are every time guns have been allowed, concealed-carry has been allowed, the crime rate has gone down.”

--Rep. Louie Gohmert (R-Tex.), on “Fox News Sunday,” Dec. 16, 2012

In the wake of the tragedy at Sandy Hook Elementary School in Newtown, Conn., a number of lawmakers have pushed for new gun-control legislation. But some gun-control foes, such as Rep. Louie Gohmert, have argued that instead more guns, not more controls, are needed.

Appearing on Fox News Sunday, Gohmert said of slain principal Dawn Hochsprung: “I wish to God she had had an M-4 [assault rifle] in her office, locked up so when she heard gunfire, she pulls it out and she didn’t have to lunge heroically with nothing in her hands, but she takes him out, takes his head off before he can kill those precious kids.”

Laying aside the question of armed teachers in schools, we were interested in Gohmert’s sweeping statement that laws that have allowed concealed weapons have always resulted in a decline in crime rates. Can such a cause-and-effect link be established?

The Facts

The National Rifle Association says that, by its definition, there are now 41 states that have “right-to-carry” laws. “Since 1991, when violent crime peaked in the U.S., 24 states have adopted ‘shall issue’ laws, replacing laws that prohibited carrying or that issued carry permits on a very restrictive basis; many other federal, state, and local gun control laws have been eliminated or made less restrictive; and the number of privately-owned guns has risen by about 100 million,” the organization says on its Web site.

The NRA then cites the research of economists John Lott and David Mustard. Lott wrote a book, first published in 1998 and now in its third edition, titled “More Guns, Less Crime: Understanding Crime and Gun Control Laws.” In the book, Lott used a massive data set of U.S. crime and socioeconomic statistics to argue that detailed analysis showed a link between rate of crime and right-to-carry laws in states and counties.

But Lott’s conclusions are controversial — and other academics have criticized his work as either simplistic or subject to empirical errors. In 2004, a committee of the National Research Council of the National Academies devoted a chapter in a report titled “Firearms and Violence: A Critical Review” examining Lott’s research. The report concluded:

No link between right-to-carry laws and changes in crime is apparent in the raw data, even in the initial sample; it is only once numerous covariates are included that the negative results in the early data emerge. While the trend models show a reduction in the crime growth rate following the adoption of right-to-carry laws, these trend reductions occur long after law adoption, casting serious doubt on the proposition that the trend models estimated in the literature reflect effects of the law change. Finally, some of the point estimates are imprecise. Thus, the committee concludes that with the current evidence it is not possible to determine that there is a causal link between the passage of right-to-carry laws and crime rates.

Still, it is worth noting that one committee member, the late James Q. Wilson, dissented from this chapter, noting that his reading of the data showed that the laws did result in a decline in the murder rate. (He also observed that the laws did not appear to cause an increase in the crime rate, as opponents had warned.) But there was general agreement by the committee, including Wilson, that it was impossible to find strong links between the enactment of right-to-carry laws and violent and property crime in general and rape, aggravated assault, auto theft, burglary and larceny in particular.

Another sustained critique was by Ian Ayres and John J. Donohue III, who wrote a 2003 paper titled “Shooting Down the More Guns, Less Crime Hypothesis.” They said:

We conclude that Lott and Mustard have made an important scholarly contribution in establishing that these laws have not led to the massive bloodbath of death and injury that some of their opponents feared. On the other hand, we find that the statistical evidence that these laws have reduced crime is limited, sporadic, and extraordinarily fragile. Minor changes of specifications can generate wide shifts in the estimated effects of these laws, and some of the most persistent findings — such as the association of shall-issue laws with increases in (or no effect on) robbery and with substantial increases in various types of property crime — are not consistent with any plausible theory of deterrence.

It is beyond the scope of this column to examine all of the critiques of Lott’s work, but a useful summary (and Lott’s response) appeared in the magazine Regulation two years ago. The review concluded that serious questions had been raised about Lott’s work but also that right-to-carry laws had “lowered violent crime somewhat but not a terribly consistent manner.”

The difficulty academics have in reaching a firm conclusion illustrates why in general politicians should avoid making such blunt causal connections.

Last year, we knocked Vice President Biden for claiming that fewer police officers result in more crime. We cited University of Chicago economist Steven D. Levitt, who in 2004 examined 10 possible factors — including more right-to-carry laws — for why crime fell in the 1990s. Levitt said four explanations held up under scrutiny: increases in the number of police, an increase in a rising prison population, the receding crack epidemic and even the legalization of abortion (which resulted in fewer unwanted births). By contrast, “there appears to be little basis for believing that concealed weapons laws have had an appreciable impact on crime.” (We should note that Levitt was a primary author of the chapter in the National Research Council report.)

(International comparisons are always problematic, given cultural differences, but gun-control advocates might argue that more restrictions would be even more effective in the long run. There are virtually no shooting deaths in Japan, which has very strict controls on gun ownership, as detailed by our colleague Max Fisher in the Atlantic last year.)

We sent a query to Gohmert’s aides, seeking additional evidence for his statement, but did not receive a response.

Update: Lott notes that, by his assessment, a majority of the research in referred academic publications supports his point of view. In a 2012 article for the Maryland Law Review, Lott listed 18 studies that found such laws reduced violent crime, ten that said it has no discernable effect and one that found it increased violent crime.

“The debate has been between those who say that it reduces crime and those who say it has no effect,” he noted. “Very few debates are divided that way.”

The Pinocchio Test

Gohmert’s statement was declarative and sweeping: “The facts are every time guns have been allowed, concealed-carry has been allowed, the crime rate has gone down.”

The actual evidence is much murkier — and in dispute. Certainly, it appears such laws have not increased the crime rate, as opponents had feared, but it is equally a stretch to say such laws are a slam-dunk reason for why crimes have decreased. Even those sympathetic to Lott’s research suggest that any decline in the crime rate from right-to-carry laws is more sporadic — as opposed to Gohmert’s claim that crime rate always goes down.

Moreover, even if one could prove a definitive link, other factors certainly play a role in reducing crime and should be acknowledged. (Update: We wavered between Two and Three Pinocchios, but the Washington Examiner argues our final ruling is “unfair” given the murkiness of the evidence: “The research is good, but it doesn’t jibe with the conclusion.”)

Three Pinocchios

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