Check out Jeffrey Scott Shapiro's "A Gun Ban That Misfired" in today's WSJ. Mr. Shapiro was a criminal prosecutor for the District of Columbia from 2007-09. "As a former prosecutor in Washington, D.C., who enforced firearms and ammunition cases while a severe local gun ban was still in effect, I am skeptical of the benefits that many imagine will result from additional gun-control efforts. I dislike guns, but I believe that a nationwide firearms crackdown would place an undue burden on law enforcement and endanger civil liberties while potentially increasing crime.... The gun ban had an unintended effect: It emboldened criminals because they knew that law-abiding District residents were unarmed and powerless to defend themselves. Violent crime increased after the law was enacted, with homicides rising to 369 in 1988, from 188 in 1976 when the ban started. By 1993, annual homicides had reached 454.... Since the gun ban was struck down, murders in the District have steadily gone down, from 186 in 2008 to 88 in 2012, the lowest number since the law was enacted in 1976. The decline resulted from a variety of factors, but losing the gun ban certainly did not produce the rise in murders that many might have expected...."