from the Salon article The answer is not more guns
If Lott’s work can be discarded, the other key evidence for the more guns, less crime camp comes from criminologists Gary Kleck and Marc Gertz, whose work in the 1990s argued that there are between 800,000 and 2.5 million defensive uses of guns in America every year. The number has been widely touted by gun-rights activists, but strongly criticized by other scholars.
Indeed, studies commissioned by the Department of Justice using different sets of more rigorous data put the number at 83,000 or 108,000, alternatively. In his essay, Goldberg quickly abandons the 2.5 million figure and seems to settle on the 108,000 level, which is 23 times lower than the Kleck-Gertz top number.
Harvard economist David Hemenway has been especially critical of Kleck-Gertz, pointing out “serious methodological deficiencies” in their numbers. The data came from a national telephone survey of 5,000 households, which found that about .6 percent said they had used guns to defend themselves in the past year. Assuming that proportion held true for all Americans households, they extrapolated from their sample to find the 2.5 million figure.
Beyond the mathematical issues with that approach, and sampling problems in their survey, Hemenway said the researchers were too credulous in believing respondents. For instance, he pointed to a poll that found that 6 percent of Americans said they had had personal contact with aliens. “The ABC News/Washington Post data on aliens are as good as or better,” Hemenway quipped.
But perhaps the biggest problem with the Kleck-Gertz numbers is that one person’s self-defense is another person’s murder, as the case of George Zimmerman and Trayvon Martin demonstrated. Hemenway and a colleague conducted their own survey and then asked five criminal court judges to review their data to determine the legality of the incidents of defensive gun use reported by respondents. “A majority of the reported self-defense gun uses were rated as probably illegal by a majority of judges,” they found.
The conclusion: “Guns are used to threaten and intimidate far more often than they are used in self-defense.”