Nov. 20 (Bloomberg) -- The U.S. Supreme Court will consider whether individuals have a constitutional right to own firearms, agreeing to decide an election-year fight over the District of Columbia's decades-old handgun ban.

A ruling against Washington would give gun-rights advocates a long-sought legal victory and raise questions about weapons restrictions in New York, Chicago and other cities. The high court has never directly said whether the Constitution's Second Amendment covers people who don't belong to a state-run militia.

The justices will review a lower court decision that struck down Washington's ban and said the Second Amendment protects individuals against unreasonable restrictions on their right to own firearms. The decision marked the first time a federal appeals court had ever voided a law on Second Amendment grounds.

``Having a handgun, whether in the home or outside it, comes at the expense of the safety of those who may be victims,'' Washington and its mayor, Adrian Fenty, argued in the appeal. ``Whatever right the Second Amendment guarantees, it does not require the district to stand by while its citizens die.''

Washington's 31-year-old gun law, perhaps the strictest in the nation, bars most residents from owning handguns and requires all legally owned firearms to be kept unloaded and either disassembled or under trigger lock. Six district residents challenged the law, some saying they want to keep handguns in their homes for self-defense purposes.

`Functional Firearms'

The restrictions ``amount to a complete prohibition of all functional firearms within the home,'' lawyers for the residents argued. ``The challenged laws are thus an absolute negation of the people's right to keep arms.''

The residents joined the city in urging the Supreme Court to hear the district's appeal.

The justices will hear arguments next year and most likely rule in June, in the midst of the U.S. presidential campaign. The case promises to be one of the highlights of a nine-month term that already includes disputes over the rights of Guantanamo Bay inmates and the legality of executions by lethal injection.

The Second Amendment says: ``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.''

How the court will construe that language is largely guesswork. The justices last considered the Second Amendment in 1939, issuing a ruling that both sides in the debate now claim as support for their position.

Thomas and Scalia

Justice Clarence Thomas hinted in a 1997 case that he was receptive to the individual-rights approach, and Justice Antonin Scalia made similar suggestions in his 1997 book. Chief Justice John Roberts said during his 2005 confirmation hearings that the 1939 ruling ``sidestepped'' the individual-rights question.

The U.S. Court of Appeals for the D.C. Circuit ruled in March that Washington can't ban all handgun possession in the home. The 2-1 decision said the Second Amendment protects a right that ``existed prior to the formation of the new government under the Constitution and was premised on the private use of arms for activities such as hunting and self- defense.''

Washington's decision to appeal to the high court represented a gamble for gun-control advocates. The lower court decision applied only to the nation's capital, while the Supreme Court decision probably will have nationwide impact.

Kennedy's Role

``We are nervous,'' said Paul Helmke, president of the Brady Campaign to Prevent Gun Violence, a Washington-based group that chose not to join the city in asking the court to hear the case. Helmke said in an interview the case might produce a 5-4 decision, with swing vote Justice Anthony Kennedy determining the outcome.

In a statement, Helmke said the ruling will be ``the most important decision on guns in nearly 70 years and maybe the most important ever regarding the Second Amendment.''

The National Rifle Association similarly didn't take a position on whether the court should get involved. The organization said in a statement that it plans to file a brief before the court hears arguments.

Washington contends that the Second Amendment applies only to weapons used in the service of state-run militias, such as National Guard units. The city also argues that the amendment restricts only the federal government, not the states or the District of Columbia.

`Reasonable' Limit

In a third line of argument, Washington contends that even if residents can invoke Second Amendment rights, the handgun ban should be upheld as a ``reasonable'' limit on those rights. The city says it doesn't bar ownership of rifles or shotguns. The handgun ban doesn't apply to retired police officers.

The justices first considered the gun case at their private conference on Nov. 9. They postponed taking any action until they had met again this morning and had modified the question presented by Washington's appeal. The court will consider the rights of individuals ``who wish to keep handguns and other firearms for private use in their homes.''

The notion that the Second Amendment protects individual rights has gained credence among scholars in recent decades. Harvard's Laurence Tribe and Yale's Akhil Reed Amar are among the constitutional law professors who have taken that view. The Bush administration has also embraced the individual-rights approach.

Still, most U.S. appeals courts to consider the issue have said the Second Amendment is aimed at protecting state militias. Only the D.C. Circuit and the New Orleans-based 5th Circuit have taken the individual-rights approach.

Reducing Crime

Critics say the Washington law has been ineffective in reducing violent crime. The number of murders in the city peaked at 482 in 1991, up from 188 in 1976. The city recorded 169 homicides last year. Police said today that about 80 percent of the district's murders involve handguns.

The group challenging Washington's restrictions originally consisted of six city residents. The D.C. Circuit said only one member of that group, Dick Heller, could sue because the others hadn't applied for a weapons permit. Heller, who works as an armed security guard at a federal government building in Washington, says he wants to keep a handgun in his home.

``D.C. has high-crime areas,'' said another member of the group, Gillian St. Lawrence, who said she keeps a disassembled shotgun in her home. ``For most of the 30 years that this law has been in effect, it's been the murder capital of America.''

The case is District of Columbia v. Heller, 07-290.

To contact the reporter on this story: Greg Stohr in Washington at gstohr@bloomberg.net.

Last Updated: November 20, 2007 16:10 EST