Some companies in several states could be barred from telling their employees to keep their guns at home if lawmakers prevail in a battle that pits gun rights advocates against private businesses. At least six states — Alaska, Kansas, Kentucky, Minnesota, Mississippi and Oklahoma — have passed laws that bar some employers from forbidding workers to leave guns locked in their cars in company lots but don't give workers the right to carry firearms into the actual workplace. Now, several more states are considering such laws. Supporters say licensed gun owners should have access to their weapons in case they need them for self-defense on the trek to and from home. If employers can ban guns from workers' cars, "it would be a wrecking ball to the Second Amendment," which governs the right to bear arms, says Wayne LaPierre, executive vice president of the National Rifle Association (NRA). Many business organizations and gun-control advocates argue, however, that such laws clash with employers' responsibility to maintain safe workplaces and their right to determine what to allow on their private property. These laws are "a systematic attempt to force guns into every nook and cranny in society and prohibit anyone, whether it's private employers (or) college campuses … from barring guns from their premises," says Brian Siebel, senior attorney for the Brady Center to Prevent Gun Violence. There were 516 workplace homicides — 417 of them caused by gunfire — in 2006, the most recent tally available, according to the Bureau of Labor Statistics. "There's certainly no need to allow guns in these parking lots," Siebel says. "The increased risks are obvious." The moves to ensure that workers can have guns locked up in workplace parking lots come at a time of high-stakes debate over gun rights. The Supreme Court is likely to rule this year on whether Washington, D.C., can continue its 32-year-old ban on residents owning handguns. States considering bills to expand workers' gun rights: •Arizona. State Rep. Jonathan Paton, a Republican, says he sponsored his bill last month after a constituent told him he drives isolated roads to work but is not allowed to keep a handgun in his car. "It just comes down to the right of self-defense," Paton says. •Tennessee. The proposed legislation, introduced in January, excludes correctional facilities and properties owned by the federal government. An amendment may be added to allow businesses that have secure parking areas that are less prone to crime to ban guns there. "I respect property and business rights," says state Sen. Paul Stanley, a Republican sponsoring the bill. "But I also think that some issues need to overshadow this. … We have a right to keep and bear arms." •Georgia. The legislature is considering a bill to allow licensed gun owners to leave their gun in a locked vehicle on their company's parking lot if the employer permits it. The NRA and other gun rights advocates began pushing the parking lot legislation after Weyerhaeuser in 2002 fired several of its Oklahoma employees when guns were found in their vehicles, violating company policy. Two years later, Oklahoma's Legislature passed a law prohibiting employersfrom banning guns locked inside parked cars. A federal judge in October issued a permanent injunction against the law, a decision being appealed. The laws are being considered as the number of states that allow a law-abiding adult to carry a concealed gun in public has reached 40, legal experts say. "It's part of the general movement to allow people to have guns for self-defense not only at home, but in public places where they're most likely needed," says Eugene Volokh, a professor at UCLA School of Law who specializes in gun policy. He says employers face more constraints than in the past. LaPierre says laws that allow people holding proper permits to carry firearms for personal protection are largely nullified when employers can prohibit workers from locking a gun in their parked cars. "Saying you can protect yourself with a firearm when you get off work late at night is meaningless if you can't keep it in the trunk of your car when you're at work," he says. Some constitutional law experts say the Second Amendment does not give gun owners a constitutionally protected right to carry their weapons onto somebody else's private property when the owner doesn't want them to. "If I said to somebody, 'You can't bring your gun into my house,' that person's rights wouldn't be violated," says Mark Tushnet, a Harvard Law School professor. The American Bar Association sides with business owners, supporting "the traditional property rights of private employers and other private property owners to exclude" people with firearms. Steve Halverson, head of Jacksonville-based construction company Haskell, says business owners should be able to decide whether to allow weapons in their parking lots. "I object to anyone telling me that we can't … take steps necessary to protect our employees," says Halverson, who enforces safety measures ranging from banning guns to requiring workers to wear hard hats. "The context is workplace safety, and that's why it's important," he says. "The larger issue is property rights, and whether you as a homeowner and I as a business owner ought to have the right to say what comes onto our property." Enlarge By Jim Mone, AP An employee at a sporting goods store in St. Paul. displays handguns that are popular sellers in May 2003. 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