CHICAGO -- It's Christmas and Robert Sherman is on a crusade, but this crusade has nothing to do with religion.

Sherman, national spokesman for American Atheists and director of the Illinois chapter, is fighting to remove nativity scenes from government property.

He has gone to 13 Chicago suburbs that display creches in village halls or public parks -- first asking city councils to remove the displays, then threatening legal action.

"Nativity scenes create a climate where people think that we're a Christian nation," Sherman said. "It creates a misimpression that we're supposed to be Christian."

Last week, he complained to the Illinois Toll Highway Authority about a creche along the Tri-State Tollway. The agency has since removed Mary and Joseph, leaving two choirboys, Santa Claus and a "Merry Christmas" sign. Agency Director Thomas Morsch said fear of a lawsuit prompted this decision.

"The courts have to be the last ones to rule. We have to obey the laws. Although I may personally feel it's picky, you can't say a person is wrong for what he's doing," Morsch said.

Courts have ruled variously on whether nativities on government property violate the constitutional separation of church and state. In 1984, the U.S. Supreme Court ruled 5 to 4 that a Pawtucket, R.I., display depicting the birth of Christ did not indicate a government preference for Christianity. The court upheld the use of city funds to pay for the display.

But Sherman observes that the display was on private property, a distinction he sees as important.

Chicago's City Hall has no nativity scene this year because the 7th U.S. Circuit Court of Appeals ruled last August that the traditional creche was unconstitutional.

Of the towns contacted by Sherman, Winthrop Harbor and Zion agreed to move their creches to private property. Northbrook said no creche would be erected.

In Mundelein (population 18,000), Mayor Colin McRae said the village lawyer has not told him to remove the creche. "Until that time, it's going to stay up," McRae said. "When I look at that creche, I see a symbol that says peace and good will to all men and beasts."

The Knights of Columbus have displayed a creche in the town square of north suburban Libertyville for more than 20 years, according to Mayor Paul Neal, who said he did not plan to remove it.

"No one's objected to it before. The parks are for people of this community to use. Everyone in this community resents an outsider telling us how we have to live," Neal said.

Sherman counters that he speaks for the "silent minority" of people -- atheists and other non-Christians in these towns who are afraid to voice their objections.

"Because of the level of religious intimidation suffered by atheists, it takes a leader from the area who has the courage and financial resources to bring these issue to a head," Sherman said.

Sherman, 34, owner of a computer and electronics firm, first gained notoriety in Illinois in 1986 when he sued Zion, Ill., for the city's use of the Christian cross in its seal. The case is pending in federal court.

He is waging a constitutional battle, he said, because "the government is not allowed to pick a religion. Everyone has the right to their own personal opinion about religion. We just don't want the government to do that."

Sherman, an atheist for over 20 years, said he is not offended by creches on private property. "It's just a few figurines or lumps of clay," he said.

What bothers him, Sherman said, is that "while some people argue that creches symbolize a holiday season, the primary effect is to unconstitutionally link government with a particular religion . . . . The Constitution is not a cafeteria meal where you can pick and choose what rules you'll abide by."