A federal judge yesterday temporarily stopped the U.S. Park Police from arresting people for laying down their belongings or protest signs in front of the White House.

Responding to a request from the American Civil Liberties Union, Judge William B. Bryant issued a temporary restraining order barring the Interior Department for 10 days from enforcing a new emergency regulation that restricts demonstrators' signs in front of the White House to hand-held ones and requires people to carry their other belongings or submit them to a search.

The regulation, which took effect April 22, is intended to make it more difficult for potential terrorists to conceal explosives on the sidewalk in front of the White House or vault over the iron fence into the White House grounds from Pennsylvania Avenue, according to the government.

Representing the ACLU, Arthur Spitzer told Bryant in a hearing yesterday that the government had failed to show any emergency that would allow it to put the regulation into effect without first getting comments from the public, as required by law.

Contending that the regulation is vague and that it conflicts with demonstrators' First Amendment right to express themselves, Spitzer said, "They the regulations are wholly arbitrary and capricious and virtually illogical . . . . They've gone wild in writing the regulation here."

He suggested the wording of the regulation would subject to arrest tourists who park baby carriages along the fence or the members of the White House Vigil for the ERA Committee--one of the ACLU's clients--for unfurling a cloth banner because it is held by two people.

James C. Lindsey, deputy chief of the Park Police, said the regulations were prompted by Norman Mayer's threat last December to blow up Washington Monument and by the recent bombing of the American Embassy in Beirut. He also said a sign can be used like a stepladder to help a would-be assassin jump the fence.

"It seems to me that you have some legitimate concerns, but the regulations don't strike at that," Bryant said. He suggested that the Park Police guarding the street side of the fence, or the Executive Protective Service guarding the yard, should be able to see concealed materials.