DENVER - Two people who say they were ejected from a taxpayer-financed appearance by President Bush in March because of an antiwar bumper sticker filed a federal lawsuit here on Monday, charging that event staff members and federal employees broke the law.

The suit, filed in Federal District Court by lawyers for the American Civil Liberties Union, could transform what had been a public-relations thorn for the Bush administration into a legal thicket. A.C.L.U. lawyers said they would pursue in particular the question of who gave orders to workers at the event, held March 21 at the Wings Over the Rockies Air and Space Museum in Denver.

The suit could also put the United States Secret Service in the position of having to point fingers, because one of the crucial elements of the suit, A.C.L.U. lawyers said, could come from Secret Service testimony.

Martha Tierney, a Denver lawyer who is working in cooperation with the A.C.L.U., said at a news conference that the agent in charge of the Secret Service's Denver office, Lon Garner, told the plaintiffs and their lawyers that a bumper sticker saying "No More Blood for Oil" was the impetus for the ejections.

Mr. Garner said, according to Ms. Tierney, that a person working or volunteering at the event spotted the bumper sticker, and that the people who actually ushered the plaintiffs out were not Secret Service agents.

Mr. Garner declined to comment. A spokesman at the Secret Service headquarters in Washington, Thomas Mazur, said he could not comment on current litigation.

The suit names two local event workers or volunteers, Michael Casper and Jay Bob Klinkerman, as defendants and up to five "John or Jane Does" who the suit says were either federal employees or acting at the direction of federal employees in overseeing the president's visit.

Mr. Casper, who has been identified in local news accounts as a government employee at the Byron White Federal Courthouse in Denver, did not return telephone calls to his office, cellphone or home. Mr. Klinkerman did not return telephone or e-mail messages.

Mr. Bush came here in March to talk about overhauling Social Security, and the public was invited. The plaintiffs - Leslie Weise, 40, a corporate lawyer from Boulder, and Alex Young, 26, an information technology specialist from Denver - said they obtained tickets from their congressman's office and had no intention of disrupting the event. They arrived together in Ms. Weise's car, which bore the bumper sticker.

"We did absolutely nothing wrong," Ms. Weise said at the news conference. "We had every right to be there."

According to the suit, Ms. Weise was singled out from the moment she entered the museum. At the security checkpoint, she was asked to step aside, and Mr. Klinkerman, who identified himself as a volunteer, told her to wait for someone from the Secret Service, the suit said.

"Soon, defendant Casper arrived," the suit said. "Defendant Casper wore a dark blue suit, an earpiece and a lapel pin. As he approached, defendant Klinkerman said, 'That's him,' or 'Here he comes.' "

Mr. Casper told Ms. Weise she had been "ID'd," the suit says, and that if she or her friends tried any "funny stuff," they would be arrested. It adds that Mr. Casper then stepped away and apparently consulted one or more people by his earpiece radio, and returned to say they would have to leave after all.

Mr. Young, Ms. Weise and a third person ejected from the museum, Karen Bauer, an office worker - all of whom volunteered for Senator John Kerry, the Democratic presidential nominee in 2004 - have been speaking out, traveling to Washington in June, for instance, to press for an investigation.

The lawsuit says that Mr. Casper, Mr. Klinkerman and the unknown federal employees violated the plaintiffs' First and Fourth Amendment rights, and asks the court to award "damages and such other relief as is just and proper."

Copyright 2005 The New York Times Company

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