Most of the weapons characterized as "assault weapons" are variants of the AR-15, said Adam Winkler, a law professor at University of California-Los Angeles and author of "Gunfight: The Battle over the Right to Bear Arms in America." "I have an AR-15 at home and I haven't hurt anybody and I don't intend to do it," Graham declared on Wednesday at a Judiciary Committee hearing. It was the first to deal with gun violence since a gunman last month killed 26 people at a Newtown elementary school, including 20 children. Graham opposes reinstating a ban on assault weapons. The conservative South Carolina Republican did not explain why he had the weapon, but said such a gun could be useful for protection if lawlessness or rioting broke out in his neighborhood. "I think I would be better off protecting my business or my family if there was law-and-order breakdown in my community, people roaming around my neighborhood, to have the AR-15, and I don't think that makes me an unreasonable person," Graham said. The Bushmaster rifle, which police have said was the weapon used in the Newtown shootings, is often referred to as an AR-15, although it is not manufactured by ArmaLite, the original maker of the AR-15, Winkler said. "AR-15 has become shorthand for this style of rifle. Gun enthusiasts don't like the term 'assault weapon,' so AR-15 has become the shorthand," Winkler said.