More Guns, Less Crime

More Guns, Less Crime‘ is a book by economist John Lott that says violent crime rates go down when states permit the concealed carry of guns. He presents the results of his statistical analysis of crime data for every county in the United States during 29 years from 1977 to 2005. The book examines city, county and state level data from the entire United States and measures the impact of 11 different types of gun control laws on crime rates. The book expands on an earlier study published in 1997 by Lott and his co-author David Mustard in ‘The Journal of Legal Studies.’

Lott also examines the effects of gun control laws, including the Brady Law. His conclusion is that ‘shall issue’ laws, which allow citizens to carry concealed weapons, steadily decrease violent crime. He explains that this result makes sense because criminals are deterred by the risk of attacking an armed victim. As more citizens arm themselves, the danger to criminals increases. Lott also examines the effects of training requirements on crime rate and accident rate. He finds that training requirements have very little effect on both crime rates and accident rates.

Partially in response to Lott’s book, a sixteen-member panel of the United States National Research Council was convened to address the issue of whether right-to-carry laws influenced crime rate. In 2004 they issued the report ‘Firearms and Violence: A Critical Review’ which examined Lott’s statistical methods in detail, including computation of the statistical uncertainties involved, and wrote: ‘The committee found that answers to some of the most pressing questions cannot be addressed with existing data and research methods, however well designed. For example, despite a large body of research, the committee found no credible evidence that the passage of right-to-carry laws decreases or increases violent crime, and there is almost no empirical evidence that the more than 80 prevention programs focused on gun-related violence have had any effect on children’s behavior, knowledge, attitudes, or beliefs about firearms. The committee found that the data available on these questions are too weak to support unambiguous conclusions or strong policy statements.’

A 2010 re-examination of Lott’s work and the NRC’s analysis, as well as six years of additional data, found that: ‘We buttress the NRC’s cautious conclusion by showing how sensitive the estimated impact of RTC laws is to different data periods, the use of state versus county data, particular specifications, and the decision to control for state trends. Overall, the most consistent, albeit not uniform, finding to emerge from the array of models is that aggravated assault rises when RTC laws are adopted. For every other crime category, there is little or no indication of any consistent RTC impact on crime.’

Some academic studies that have rejected Lott’s conclusions, and most contend that there seems to be little or no effect on crime from the passage of license-to-carry laws. Some, such as Donohue’s 2003 study, find a temporary increase in aggravated assaults. Rutgers sociology professor Ted Goertzel stated that ‘Lott’s massive data set was simply unsuitable for his task,’ and that he ‘compar[ed] trends in Idaho and West Virginia and Mississippi with trends in Washington, D.C. and New York City’ without proper statistical controls. He points out that econometric methods (such as the Lott & Mustard RTC study or the Levitt & Donohue abortion study) are susceptible to misuse and can even become junk science.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.