Waving a chromed semiautomatic pistol, the robber pushed into the building in the bustling Five Points neighborhood of Columbia, S.C., just before 11 p.m. on April 11, 2009. Gimme what you got! he yelled, his gun hand trembling.

Attorney Jim Corley was one of four people in the room, the lounge area of a 12-step recovery groups meeting hall. He said, Give me your wallet, Corley recalled. So I reached around to my back pocket and gave him what was there.

Unfortunately for the gunman, later identified as Kayson Helms, 18, of Edison, N.J., that was Corleys tiny Kel-Tec .32, hidden in a wallet holster and loaded with a half-dozen hollow points. Corley fired once into the robbers abdomen. The young man turned. Corley fired twice more, hitting him in the neck and again in the torso. Helms ran into the night and collapsed to die on a railroad embankment 100 feet away.

Reports filed by officers who arrived at the scene a short time later called it an exceptionally clear case of justifiable homicide. Following South Carolinas Castle Doctrine, which allows the use of deadly force in self-defense, police did not arrest Corley. They did not interrogate him. Corley was offered the opportunity to make a voluntary statement, which he did.

Helms friends and relatives were left to mourn, barred by the same Castle Doctrine from filing a civil lawsuit.

Jim Corley became an unintentional spokesman for a burgeoning movement of millions of Americans who secretly and legally pack pistols in waistbands, under jackets, strapped to ankles, stashed in purses or like Corley tucked in hip pockets.

From its beginnings in the 1980s, the right-to-carry movement has succeeded in boosting the number of licensed concealed-gun carriers from fewer than 1 million to a record 6 million today, according to estimates from gun-rights groups that are supported by msnbc.coms research. And while hotly debated, the effect of this dramatic increase is largely unknown.

Gun enthusiasts claim a link between more private citizens carrying concealed weapons and the nations dramatic decrease in violent crime. Gun-control activists argue that concealed-carry permits are being handed out to people who should never get them, sometimes resulting in tragic, needless shootings.

Effect on crime is hotly debated
But even with the push to expand concealed-carry rights now in its third decade, no scientific studies have reached any widely accepted conclusions about the movements effect on crime or personal safety.

Statistics from the national Centers for Disease Control do indicate that the murder and mayhem predicted by many opponents of concealed-carry laws have not come to pass. But even that point, while celebrated by gun-rights activists and conceded by some concealed-carry opponents, is disputed by others.

Both sides do agree on one thing: More Americans than ever are carrying hidden guns.

Firearms laws have been growing more relaxed across the United States for years. Gun-control activists have failed in efforts to re-enact the nationwide ban on certain semiautomatic rifles they call assault weapons. They were unable to block a change in federal law, signed by President Obama this year, which allows guns to be carried in national parks. And they watched in dismay as the U.S. Supreme Court ruled in June 2008 that the Second Amendment grants residents of Washington, D.C., the right to own and keep loaded handguns in their homes.

Weve had a very good run, said Andrew Arulanandam, chief spokesman for the 4 million-member National Rifle Association, the nations largest and most powerful voice for gun rights.

Its a run that has often been paced by the work of the NRA and its allies on concealed-weapons laws.





INTERACTIVE
Going For Their Guns
See which states offer "shall issue" concealed-weapons permits; "may issue" and "no issue" states also are shown.


In a little more than 20 years, the concealed-carry movement has won changes in scores of laws across the nation to boost from nine to 37 the number of shall issue states in which civilians must be given concealed-carry permits, known as CCWs, generally if they are 21 or older, do not have a criminal record and are willing to submit to fingerprinting and a background check. In two more states, Alaska and Vermont, most adults may carry concealed handguns without obtaining permits.

The movement's successes have energized some gun-rights activists to push for laws that further increase their ability to carry weapons, even when those laws trump private property and states rights.

The reasons for the push to loosen concealed carry laws are themselves open to debate.

Kristen Rand, legislative director for the Violence Policy Center, a gun-control group, said the movement has to do with selling more guns. While it was pushed by groups like the NRA, it also dovetailed with the gun industrys desperate need to find a new market.

Their efforts at reaching out to minorities and women have failed, said Rand, whose group advocates banning all handguns and some rifles but believes sporting rifles and shotguns should remain legal. The industry constantly has to look for a way to make a guy who already owns 15 guns buy a new one.