At the end of June, the Supreme Court, in a case called District of Columbia v. Heller, invalidated the District's ban on the private ownership of pistols. It did so in the name of the Second Amendment to the Constitution. The decision was the most noteworthy of the Court's recent term. It is questionable in both method and result, and it is evidence that the Supreme Court, in deciding constitutional cases, exercises a freewheeling discretion strongly flavored with ideology.

The majority opinion, by Justice Antonin Scalia, concluded that the original, and therefore the authoritative, meaning of the Second Amendment is that Americans are entitled to possess pistols (and perhaps other weapons) for the defense of their homes. Scalia's entire analysis rests on this interpretive method, which denies the legitimacy of flexible interpretation designed to adapt the Constitution (so far as the text permits) to current conditions. The irony is that the "originalist" method would have yielded the opposite result.

The Second Amendment, part of the Bill of Rights added to the original Constitution in 1791, states: "A well regulated Militia being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed." In other words: since a militia, provided that it is well regulated, is a very good thing for a free state to have, the federal government must not be allowed to castrate it by forbidding the people of the United States to possess weapons. For then the militia would have no weapons, and an unarmed militia is an oxymoron.

Politically conscious Americans in the late eighteenth century feared standing armies, having fought the British army in the Revolution, and feared centralized government (as in Britain); and on both counts they wanted to make sure that the states would be allowed to have armed militias. The federal government could regulate them but not disarm them. The fear was that in the absence of such a provision in the Bill of Rights, the provision in Article I of the Constitution authorizing Congress to organize, arm, discipline, and call into service "the Militia" (a term that embraces the state militias, because the same provision reserves the right to train and officer "the Militia" to the respective states) would enable Congress to disarm them. That fear surfaced in the debates over the ratification of the original Constitution and was, as Justice John Paul Stevens's dissenting opinion explains, the motivation for the Second Amendment.

The text of the amendment, whether viewed alone or in light of the concerns that actuated its adoption, creates no right to the private possession of guns for hunting or other sport, or for the defense of person or property. It is doubtful that the amendment could even be thought to require that members of state militias be allowed to keep weapons in their homes, since that would reduce the militias' effectiveness. Suppose part of a state's militia was engaged in combat and needed additional weaponry. Would the militia's commander have to collect the weapons from the homes of militiamen who had not been mobilized, as opposed to obtaining them from a storage facility? Since the purpose of the Second Amendment, judging from its language and background, was to assure the effectiveness of state militias, an interpretation that undermined their effectiveness by preventing states from making efficient arrangements for the storage and distribution of military weapons would not make sense.