Multiple regression analyses are rarely the subject of heated public debate or 225-page books for laypeople. But John R. Lott, Jr.'s study in the January 1997
Journal of Legal Studies showing that concealed-carry weapons permits reduced the crime rate set off a firestorm. The updated study, together with illustrative anecdotes and a short description of the political and academic response to the study, as well as responses to the responses, makes up Lott's informative
More Guns, Less Crime.
In retrospect, it perhaps should not have been surprising that increasing the number of civilians with guns would reduce crime rates. The possibility of armed victims reduces the expected benefits and increases the expected costs of criminal activity. And, at the margin at least, people respond to changes in costs, even for crime, as Nobel-Prize winning economist [TAG]Gary Becker showed long ago. Allusions to the preferences of criminals for unarmed victims have seeped into popular culture; Ringo, a British thug in Pulp Fiction, noted off-handedly why he avoided certain targets: "Bars, liquor stores, gas stations, you get your head blown off stickin' up one of them."
But Lott's actual quantification of this, in the largest and most comprehensive study of the effects of gun control to date, a study well-detailed in the book, provoked a number of attacks, ranging from the amateurish to the subtly misleading, desperate to discredit him. Lott takes the time to refute each argument; it's almost touching the way he footnotes each time he telephones an attacker who eventually hangs up on him without substantiating any of their claims.
Lott loses a little focus when he leaves his firm quantitative base; as an economist, he should know that the low number of rejected background checks under the Brady Bill doesn't demonstrate anything by itself, because some people may have been deterred from even undergoing the background check in the first place, but he attacks the bill on this ground anyway. But the conclusions that are backed by evidence--that concealed-weapons permits reduce crime, and do so at a lower cost to society than increasing the number of police or prisons--are important ones that should be considered by policymakers. --Ted Frank
On an average day in the United States, guns kill some 100 citizens and are used in about 3000 serious crimes. The policy discussion concerning this important problem in public health and criminal justice is one of America's most contentious debates.
At one extreme are those who would ban all guns. At the other are those who would increase the armament of our already heavily armed nation. The latter view is reminiscent of Archie Bunker's solution to the hijacking problem of the 1970s. "If everyone was allowed to carry guns, them hijackers wouldn't have no superiority. All you gotta do is arm all the passengers, then no hijacker would risk pullin' a rod."
An economist, John Lott, has cited Archie Bunker's solution approvingly as he weighs in on the pro-gun side of the debate. The title of this new book, More Guns, Less Crime, aptly describes his conclusions. The core of the book is a large statistical study of state "right-to-carry" laws.
Between 1985 and 1992, 10 states, primarily in the gun-dense southern and Rocky Mountain regions, moved from "may-issue" laws for carrying a concealed gun (police retain discretion about who gets a permit to carry a gun) to "shall-issue" laws (police must provide a permit to virtually anyone who is not a criminal). Comparing crime trends in states that did and did not change their laws, Lott concludes that shall-issue laws reduce violent crime.
In at least six articles published elsewhere, 10 academics found enough serious flaws in Lott's analysis to discount his findings completely. These critiques are consistent with my own experience in formulating models to assess whether state-level changes in the legal drinking age affected youth crime, which convinced me that Lott's statistical approach can sometimes yield invalid results.
The central problem is that crime moves in waves, yet Lott's analysis does not include variables that can explain these cycles. For example, he uses no variables on gangs, drug consumption, or community policing. As a result, many of Lott's findings make no sense. He finds, for example, that both increasing the rate of unemployment and reducing income reduces the rate of violent crimes and that reducing the number of black women 40 years old or older (who are rarely either perpetrators or victims of murder) substantially reduces murder rates. Indeed, according to Lott's results, getting rid of older black women will lead to a more dramatic reduction in homicide rates than increasing arrest rates or enacting shall-issue laws.
Not surprisingly, Lott's model fails several statistical specification tests designed to determine its accuracy, and other models lead to very different results. For example, Jens Ludwig, an economist at Georgetown University, uses a different statistical approach and finds that the movement to shall-issue laws has, if anything, caused homicide rates to increase.
One would have expected that, given the problems with Lott's model, it would have gone back to the drawing board. Instead, Lott decided to go public, writing this book, holding press conferences, and presenting his results as if they proved that permissive gun-carrying laws actually save lives.
Sometimes it is not the model that Lott uses but the data that are just plain wrong. For example, in the one analysis not involving carrying laws, Lott takes data on gun ownership from 1988 and 1996 voter exit polls and purports to show that higher levels of gun ownership mean less crime. According to the polling source, Voter News Service, these data cannot be used as Lott has used them -- either to determine state-level gun ownership or changes in gun ownership. For example, the data from the exit polls indicate that gun ownership rates in the United States increased an incredible 50 percent during those eight years, yet all other surveys show either no change or a decrease in the percentage of Americans who personally own firearms.
Overall, Lott deserves high marks for attempting to study an important and difficult issue and for assembling and sharing his data; he deserves failing marks for pressing policy makers to use his results despite the substantial questions that have been raised about his research. Permissive gun-carrying laws may increase or decrease crime, and knowing the effect is critical for determining appropriate policy. Unfortunately, Lott's results do not provide credible evidence one way or the other.
Lott's book is pro-gun, with an academic flavor; indeed, some training in econometrics is essential to assess his statistical approach. By contrast, Making a Killing, by Tom Diaz, an analyst at the pro-control Violence Policy Center, is more journalistic and can be evaluated more easily by a lay audience.
Making a Killing focuses on gun manufacturers and argues that in the past two decades, in an attempt to increase their sales and profits, these companies have deliberately increased the lethality of firearms. The case is made with quotations drawn from the industry itself.
The problem for the industry has been that, given reasonable care, guns don't wear out. With fewer young people growing up into the markets for traditional hunting and sport shooting, convincing people that they need more guns has required innovation and fear-nurturing advertising.
Instead of innovating in the direction of safer firearms (e.g., guns with childproof locks and load indicators), the industry chose the opposite direction. Manufacturers made guns to hold more rounds, increased the power of the rounds and the speed with which the bullets could be shot, and at the same time made guns smaller and more concealable.
Ammunition and accessories with "Rambo" appeal -- bipods, flash suppressors, grenade launchers, laser sights, and expanding bullets -- have also been increasingly offered. Ammunition has come on the market with names like "Eliminator-X," "Ultra-Mag," "Black Talon" (whose razorlike talons could tear protective gloves, exposing doctors to infectious diseases), and "Starfire," whose advertisements called it "the deadliest handgun cartridge ever developed for home or personal defense," with "fast knockdown" due to the "massive wound channel" it can create.
Foreign manufacturers have a surprisingly large role in the industry as owners of many domestic manufacturers and as exporters of large numbers of firearms to the United States. Reversing the image of U.S. cigarette manufacturers as sellers of tobacco to less regulated and less health-conscious markets in the developing world, the United States has been the dumping ground for surplus guns, such as Chinese AK-47s and Russian SKS assault rifles, that are forbidden in most other countries.
Whereas Lott presents statistics to argue, unconvincingly, for reduced regulation of firearm carrying, Diaz uses quotations from the industry to portray, convincingly, an industry in need of some sensible governmental oversight.
Reviewed by David Hemenway, Ph.D.
Copyright © 1998 Massachusetts Medical Society. All rights reserved. The New England Journal of Medicine is a registered trademark of the MMS.
