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How Often Are Firearms Used in Self-Defense?


There are approximately two million defensive gun uses (DGU's) per year by law abiding citizens. That was one of the findings in a national survey conducted by Gary Kleck, a Florida State University criminologist in 1993. Prior to Dr. Kleck's survey, thirteen other surveys indicated a range of between 800,000 to 2.5 million DGU's annually. However these surveys each had their flaws which prompted Dr. Kleck to conduct his own study specifically tailored to estimate the number of DGU's annually.

Subsequent to Kleck's study, the Department of Justice sponsored a survey in 1994 titled, Guns in America: National Survey on Private Ownership and Use of Firearms (text, PDF). Using a smaller sample size than Kleck's, this survey estimated 1.5 million DGU's annually.

There is one study, the National Crime Victimization Survey (NCVS), which in 1993, estimated 108,000 DGU's annually. Why the huge discrepancy between this survey and fourteen others?

Dr. Kleck's Answer

Why is the NCVS an unacceptable estimate of annual DGU's? Dr. Kleck states, "Equally important, those who take the NCVS-based estimates seriously have consistently ignored the most pronounced limitations of the NCVS for estimating DGU frequency. The NCVS is a non-anonymous national survey conducted by a branch of the federal government, the U.S. Bureau of the Census. Interviewers identify themselves to respondents as federal government employees, even displaying, in face-to-face contacts, an identification card with a badge. Respondents are told that the interviews are being conducted on behalf of the U.S. Department of Justice, the law enforcement branch of the federal government. As a preliminary to asking questions about crime victimization experiences, interviewers establish the address, telephone number, and full names of all occupants, age twelve and over, in each household they contact. In short, it is made very clear to respondents that they are, in effect, speaking to a law enforcement arm of the federal government, whose employees know exactly who the respondents and their family members are, where they live, and how they can be recontacted."

"It is not hard for gun-using victims interviewed in the NCVS to withhold information about their use of a gun, especially since they are never directly asked whether they used a gun for self-protection. They are asked only general questions about whether they did anything to protect themselves. In short, respondents are merely give the opportunity to volunteer the information that they have used a gun defensively. All it takes for a respondents to conceal a DGU is to simply refrain from mentioning it, i.e., to leave it out of what may be an otherwise accurate and complete account of the crime incident."

"...88% of the violent crimes which respondents [Rs] reported to NCVS interviewers in 1992 were committed away from the victim's home, i.e., in a location where it would ordinarily be a crime for the victim to even possess a gun, never mind use it defensively. Because the question about location is asked before the self-protection questions, the typical violent crime victim R has already committed himself to having been victimized in a public place before being asked what he or she did for self-protection. In short, Rs usually could not mention their defensive use of a gun without, in effect, confessing to a crime to a federal government employee."

Kleck concludes his criticism of the NCVS saying it "was not designed to estimate how often people resist crime using a gun. It was designed primarily to estimate national victimization levels; it incidentally happens to include a few self-protection questions which include response categories covering resistance with a gun. Its survey instrument has been carefully refined and evaluated over the years to do as good a job as possible in getting people to report illegal things which other people have done to them. This is the exact opposite of the task which faces anyone trying to get good DGU estimates--to get people to admit controversial and possibly illegal things which the Rs themselves have done. Therefore, it is neither surprising, nor a reflection on the survey's designers, to note that the NCVS is singularly ill-suited for estimating the prevalence or incidence of DGU. It is not credible to regard this survey as an acceptable basis for establishing, in even the roughest way, how often Americans use guns for self-protection."

(Source: Gary, Kleck and Marc Gertz, "Armed Resistance to Crime: The Prevalence and Nature of Self-Defense with a Gun," Journal of Criminal Law and Criminology 1995, Vol. 86 No. 1.)

On the Other Hand: Studying the Studies

Excerpted from

The political climate surrounding guns is so intense that studies have been done of studies that have been done about studies. Philip Cook, the director of Duke University's public policy institute, has examined the data behind the 108,000 and the 2.5 million figures and suspects the truth lies somewhere in between. "Many of the basic statistics about guns are in wide disagreement with each other depending on which source you go to," says Cook, a member of the apolitical National Consortium on Violence Research. "That's been a real puzzle to people who are trying to understand what's going on."

For Further Reading

The DGU War:

Gary Kleck and Marc Gertz, Armed Resistance to Crime: The Prevalence and Nature of Self-Defense with a Gun - "By this time there seems little legitimate scholarly reason to doubt that defensive gun use is very common in the U.S., and that it probably is substantially more common than criminal gun use. This should not come as a surprise, given that there are far more gun-owning crime victims than there are gun-owning criminals and that victimization is spread out over many different victims, while offending is more concentrated among a relatively small number of offenders."

David Hemenway, Survey Research and Self-Defense Gun Use: An Explanation of Extreme Overestimates - "Self-report surveys of rare events easily lead to huge overestimates of the true incidence of such events, particularly if the event in question has some potential social desirability. Researchers who claim that such survey incidence data are accurate must show how they have eliminated the enormous problem of false positives. Kleck and Gertz do not accept, let alone meet, this burden of proof. Their survey methodology does not ensure a Specificity rate of well over 99%. Attempts to determine the external validity of their estimates only buttress the presumption of massive overestimation. The conclusion seems inescapable: the Kleck and Gertz survey results do not provide reasonable estimates about the total amount of self-defense gun use in the United States."

Gary, Kleck and Marc Gertz, The Illegitimacy of One-Sided Speculation: Getting the Defensive Gun Use Estimate Down - "Hemenway has failed to cast even mild doubt on the accuracy of our estimates. The claim that there are huge numbers of defensive uses of guns each year in the United States has been repeatedly confirmed, and remains one of the most consistently supported assertions in the guns-violence research area."

Tom W. Smith, A Call for a Truce in the DGU War - "Neither side seems to be willing to give ground or see their opponents' point of view. This is unfortunate since there is good reason to believe that both sides are off-the-mark. . . the main shortcomings of the two approaches and some of the keys issues of contention are discussed."

Video interview with Kleck expressing his observations and opinions concerning various gun control issues and measures (2009). Magazine interview with Gary Kleck (1993).

This paper, the National Institute of Justice Research in Brief, "Guns in America: National Survey on Private Ownership and Use of Firearms", contains criticisms of Kleck's survey. [Text]~[PDF]

Kleck responds to some criticism of his study.

Lawrence Southwick, Jr., Guns and Justifiable Homicide: Deterrence and Defense - concludes there are at least 400,000 "fewer violent crimes due to civilian self-defense use of guns" and at least "800,000 violent crimes are deterred each year because of gun ownership and use by civilians."

Newspaper accounts of self-defense with a firearm.