WASHINGTON — Washington, D. C., asked the Supreme Court yesterday to save the city’s ban on handgun ownership, saying an appeals court decision overturning the prohibition “drastically departs from the mainstream of American jurisprudence.”

If the court agrees to take the case, as most legal experts believe likely, it could lead to a historic decision sometime next year on whether the ambiguously worded Second Amendment to the Constitution protects an individual’s right to own a gun or simply imparts a collective, civic right related to maintaining state militias. It is a question that has been hotly debated in the nation’s courts and legislatures for years, and a decision by the Supreme Court to settle the issue could carry broad implications for local governments and thrust gun control as an issue into the 2008 elections.

Still, the District of Columbia argues in its petition that its law — one of the toughest handgun bans in the nation — should be upheld regardless of whether the court sides with the so-called “individualist” or “collective” legal theories.

“It is eminently reasonable to permit private ownership of other types of weapons, including shotguns and rifles, but ban the easily concealed and uniquely dangerous modern handgun,” states the petition, filed by Washington, D.C., Attorney General Linda Singer. It adds: “Whatever right the Second Amendment guarantees, it does not require the District to stand by while its citizens die.”

Most petitions for review focus on why the court should take the case, but the city’s filing serves as more of a preview of its defense of the law, filled with statistics about gun violence and the harm caused to children, women, and police officers.

“No other provision of the Bill of Rights even arguably requires a government to tolerate serious physical harm on anything like the scale of the devastation worked by handguns,” the petition states.

Democratic Mayor Adrian Fenty said at a news conference outside D.C. police headquarters that the law has strong support among Washington residents. “The only possible outcome of more handguns in the home is more violence,” he said. “Our appeal will help the District of Columbia be able to continue to reduce gun violence.”

A three-judge panel of the U.S. Court of Appeals for the D.C. Circuit split 2–1 last March in throwing out the Washington, D.C., law, which prohibits handgun ownership except by active and retired law enforcement officers. It also struck down a law requiring that rifles and shotguns kept in private homes be unloaded and disassembled or bound by trigger locks.

The court ruled that the Second Amendment “protects an individual right to keep and bear arms” and that “once it is determined — as we have done — that handguns are ‘Arms’ referred to in the Second Amendment, it is not open to the District to ban them.”

The appeals court acknowledged that its decision was groundbreaking; only one other appeals court — the Fifth Circuit based in New Orleans — has recognized an individual’s right to gun ownership, and it nevertheless upheld the federal gun-control law at issue. Nine other circuits around the country have endorsed the collective right.

That split is what makes it likely the justices will accept the case, and the lawyers who brought the case on behalf of six Washington residents who wanted to overturn the gun ban also want the court to take the case.

“We support the court granting [review] and plan on responding very quickly,” said attorney Alan Gura, one of the lawyers who brought the case. Both sides expect the court could decide by November whether to hear the case, which would mean a decision could come by next summer.