People passionate about gun culture—either for or against—are a minority. To most people, the most sensible policy toward guns— what rights to own, use, and sell weapons we should recognize— is best decided by examining empirical reality, not value judgments about violence, risk, and self-reliance.
Thus, the debate about guns and gun control has been fought not just in courts and not only with constitutional interpretation as a weapon. When D.C.'s Mayor Fenty defended his city's gun policies, and later lamented their death, he stressed over and over again that laws prohibiting ownership of guns made the people of D.C. safer.
Was Fenty right? On examining the record of D.C.'s violent crime and murder rates since 1976, in comparison with its own past and with the rest of America and similarly sized cities, it doesn't look like it. Indeed, in 2003, D.C.'s murder rate was worse than Baghdad's, as noted in a Heller amicus brief from “Criminologists, Social Scientists, Other Distinguished Scholars, and the Claremont Institute,” written by gun scholar Don Kates.
In their filings, Fenty and his amid relied almost entirely on one study for its claim that D.C.'s gun laws had saved lives. The study, by Colin Loftin, published in the 1991 New England Journal of Medicine, purported to show that D.C.'s gun ban had indeed lowered homicides in D.C. The study is not sturdy enough to support all the weight Fenty placed on it. In the first place, it stops at 1987. In the second place, it takes advantage of the District's huge drops in population and concomitant drop in whole numbers of murders and violent crimes (even though the rates per capita rose enormously) to claim that lives have been saved. A critique of Loftin's study in the aforementioned Heller amicus brief from criminologists and sociologists found that if you adjusted the spans of years he used for his comparison even one year in either direction, all his supposed benefits disappeared—a sign of cherry picking for the best possible results, not objective research.