In a lawsuit filed against the city of Washington, D.C. on Thursday, the Second Amendment Foundation aims to find out.
The plaintiffs are four gun owners who were denied licenses to carry firearms in public on their person, which nearly all states permit. All U.S. states except Illinois and Wisconsin grant licenses for concealed carry, and 36 states require local police to issue the licenses unless there's a valid reason (such as a criminal history) not to do so.
The District of Columbia is a special case. Its city code says nobody may carry "either openly or concealed on or about their person, a pistol, without a license." But a law enacted in December 2008 appears to have curbed the ability of the police chief to grant those licenses.
"This really isn't about concealed carry," Alan Gottlieb, founder of the Second Amendment Foundation, told CBSNews.com in an interview on Thursday evening. "It's about being able to carry a gun, period. D.C. can prescribe some form or fashion or regulation or restrictions, but there's no way they can say you can't do it at all."
Part of the blame for this uncertainty -- how far does the Second Amendment extend? -- can be laid at the doors of no less an authority than the U.S. Supreme Court.
In the D.C. v. Heller case, the justices struck down the District's no-handguns-in-your-own-home ban on the grounds that it violated the Second Amendment, but they weren't terribly specific about what else might or might not cross the line.
Put another way, the text of the Second Amendment says that "the right of the people to keep and bear arms, shall not be infringed." Last year's Heller case dealt with the right to keep arms, but what about the right to bear arms?
The justices' majority opinion acknowledged that "at the time of the founding, as now, to 'bear' meant to 'carry,'" and that the phrase "'bear arms' was unambiguously used to refer to the carrying of weapons outside of an organized militia." Also: "We find that (the clauses) guarantee the individual right to possess and carry weapons in case of confrontation.""
Just to make things more complicated, though, the majority opinion also says: "Nothing in our opinion should be taken to cast doubt on longstanding prohibitions on the possession of firearms by felons and the mentally ill, or laws forbidding the carrying of firearms in sensitive places such as schools and government buildings, or laws imposing conditions and qualifications on the commercial sale of arms."
Permitting law-abiding Americans to carry loaded firearms on their person doesn't fall squarely into one of those categories, which has given gun rights groups some reason to be optimistic in the current lawsuit against Washington, D.C.
"We're not against all gun laws or forms of gun control here," Gottlieb said. "We're not saying that you can bring your gun to the Capitol building or the White House. But there are obviously places where you should be able to carry a gun for self-defense."
This is one case that's more likely than most to end up at the Supreme Court once again. Sonia Sotomayor was confirmed as an associate justice on Thursday, but few court watchers expect that to make a difference: as I wrote in May, both she and David Souter (her predecessor) appear to believe the Second Amendment does not protect an individual right to keep and bear arms.
Thursday's complaint filed against the District invokes two constitutional rights: First, it says that general bans on "carrying of handguns in public violate the Second Amendment to the United States Constitution"; and second, that the city's repeated refusals to grant permits "violate the rights to travel and equal protection secured by the Due Process Clause of the Fifth Amendment."
The only problem with that approach is that even though the Supreme Court said that a constitutional right to keep and bear arms exists, subsequent rulings by appellate courts have routinely said it's so limited that it doesn't have much meaning in practice. (One of those cases involved Sotomayor, and another involved a California anti-gun law.) If anti-gun types can convince judges to continue this approach, they may be able to win the next few rounds even though the Heller decision is technically the law of the land.
Declan McCullagh is a correspondent for CBSNews.com. He can be reached at firstname.lastname@example.org.