A federal judge refused Monday to let anti-abortion groups demonstrate in front of Sen. John Kerry's (search) Beacon Hill town house.

"I'm not going to second-guess the Secret Service's (search) idea of how they feel they need to protect a presidential candidate," U.S. District Judge Nathaniel Gorton (search) said.

The groups had filed a lawsuit contending the city improperly revoked their permits to demonstrate. Operation Rescue (search) and several other anti-abortion groups had planned to pray and lay roses outside Kerry's home during the Democratic National Convention (search). Kerry supports abortion rights.

Mary Jo Harris, a legal adviser to the Boston Police Department, said the city revoked the permit at the request of the Secret Service, which believed the demonstration zone was too close to Kerry's residence. She said the groups were offered another location about a block from Kerry's house. The groups turned down the offer and said they would likely not appeal the judge's decision.

"The Democratic National Convention should be welcoming free speech, not crushing it," said the Rev. Pat Mahoney, director of the Christian Defense Coalition, one of the anti-abortion groups. "It is clear regardless of whatever one's political views are, the First Amendment is not welcome here in Boston during the Democratic National Convention."

The lawsuit, filed on the first day of the Democrats' four-day convention at the FleetCenter, was the latest by protest groups seeking greater flexibility in where and when they can stage their demonstrations during the convention.

Also on Monday, the 1st U.S. Circuit Court of Appeals in Boston refused to make any changes to the fenced-in demonstration area near the FleetCenter. Civil libertarians and activist groups had sued the city, saying that confining the protests to the cramped area violates their First Amendment rights. A lower court judge had dismissed their complaint, saying unique security concerns presented by the convention made it necessary to confine the protests.

In the demonstration zone itself, several dozen protesters gathered Monday to complain about the conditions there.

Members of a group calling itself Save Our Civil Liberties quietly walked around the protest area wearing black hoods, their hands bound behind their backs with yellow cord. One protester wearing combat boots and a red Democratic National Committee T-shirt ordered them to walk, kneel and hop on one foot.

David Meieran, 42, of Pittsburgh, said they were trying to draw comparisons between the government's treatment of terrorism suspects and political protesters.

Elsewhere in the city, Buddhists held a silent vigil for peace at the Holocaust Memorial near Faneuil Hall, and rowdy supporters of perennial presidential candidate Lyndon LaRouche began singing loudly on a subway car, mocking DNC volunteers on board.

Across town, about 150 members of the Bl(A)ck Tea Society, a self-described anarchist group, gathered for protests, starting with a two-hour rally on the Boston Common, a 50-acre park once used for public hangings.

About 15 speakers railed against the Iraq War, U.S. drug policy and the imprisonment of American Indian activist Leonard Peltier before the group set off on a march through the Back Bay neighborhood. One protester collapsed, apparently from the heat, and was treated on the scene by an EMS crew.