Robert J. Spitzer, a professor of political science at the State University of New York at Cortland and the author of a 1995 book, "The Politics of Gun Control," said that efforts to expand the right to carry a gun had evolved from a "steady libertarian antigovernment attitude" in the 1980's and that they had been bolstered by Attorney General John Ashcroft's views that the Second Amendment protects an individual's right to gun ownership.
But Professor Spitzer wondered how many additional challenges might arise now that Americans have grown more concerned about public safety.
"Pro-gun groups appealed for support on an antigovernment theme, but that theme is all but dead after Sept. 11," he said. "Polls are showing a sharp increase in America's trust of government to do the right things."
For Mr. Hancock, 44, the owner of a pizza parlor and a Libertarian candidate for Congress two years ago, the change his wife encountered at the Revenue Department convinced him that the system needed adjustment. Arguing that she could be in danger without a gun in downtown Phoenix, he said: "For my wife to have to disarm to pay my taxes, oh no, no, no, no, no, no. That game is over."
To help his case in court, he entered the Revenue Department last week with a 9-millimeter Makarov on his hip (and a flock of reporters in tow). He was denied access and told to check his gun at the Capitol. On Tuesday, he filed his suit, saying the department's action violated the Second Amendment and the Arizona Constitution.
Mr. Hancock readily concedes that he has had more success making political points through the media than the courts. He could not cite a major legal victory, or even a minor one, and his latest court papers ignored that part of Arizona's concealed-weapons law that allows operators of all buildings, public and private, to deny access to gun carriers for the sake of public safety.
But his past actions, he said, have brought about changes like correcting state accounting practices and might again this time, spurring lawmakers to standardize gun-checking procedures.
Elliott Hibbs, director of the state's Administration Department, which manages the state's public buildings, pointed out that no law requires buildings to provide storage lockers.
Those that do, Mr. Hibbs said, including the Capitol, do so as a convenience for people who feel uncomfortable leaving their guns at home or in their cars.
"And even then," he said, "our people tell them not to bring them back again."