In D.C. v. Heller, the question before the Court is whether the District's prohibition of further registration of handguns, its ban on the carrying of concealed guns, and its mandate that guns kept in homes remain unloaded and either locked or disassembled violate citizens' rights that are guaranteed by the Second Amendment. Mark Tushnet writes that the Supreme Court's upcoming decision dramatizes the tension between public policy and the Constitution. David Hemenway discusses gun violence in the United States and the likely effects of the Supreme Court case D.C. v. Heller. He is a professor of health policy at the Harvard School of Public Health, Boston.