A legislative candidate who reported a racially tinged vandalism incident last weekend at his house in Prince George's County has since stopped cooperating with authorities on the advice of his lawyer, police said yesterday.

Former Orphans' Court judge David M. Valderrama told investigators that he returned home early Sunday morning from a party and found a racist slogan painted on the garage of his Fort Washington house. He said campaign posters and wooden stakes, some formed into the shape of a cross, had been burned about 15 feet from the side of his house.

Lt. Col. Robert Phillips, commander of the patrol division, which is investigating the vandalism, said yesterday that investigators twice tried to take a more detailed statement from Valderrama.

"On the first occasion, he did not keep the appointment, indicating that his schedule had prevented it," Phillips said. "On the second occasion, he said he would not give a statement on the advice of his attorney."

Sources said that Valderrama, 57, had declined to provide his fingerprints or to take a polygraph examination about the incident.

Valderrama, one of nine District 26 candidates for the state House of Delegates in Tuesday's Democratic primary, took two days off from campaigning this week, according to his headquarters. He agreed to an interview with The Washington Post yesterday, but an aide later called to cancel the meeting, citing a previous commitment.

Valderrama did not return telephone calls to his home and campaign headquarters seeking comment.

Valderrama is a prominent leader in the Washington area Filipino community. The racist graffiti disparaged his association with blacks.

Sources said authorities have questions about the reported vandalism for a variety of reasons. A flammable liquid used to ignite a pile of campaign posters was of the same type used in poolside lamps behind the Valderrama house, according to a fire department spokesman. Valderrama told investigators that he returned home just in time to discover the small, rapidly burning blaze.

Sources said investigators also questioned why the racist words were apparently written on the attached garage with a paint brush, rather than a spray can, the usual tool of graffiti vandals.

Police sources said they sought Valderrama's cooperation after finding fingerprints on cut-out letters used on a piece of hate mail allegedly sent to Valderrama, but that he declined on the advice of a lawyer.

Because the case involves both vandalism and a reported arson, police and fire investigators are involved in the investigation.

Del. Gloria Gary Lawlah, who is running on a ticket with Valderrama, said yesterday that he had been upset by the incident. "He and his family probably want some privacy," Lawlah said.