Three members of Congress who led efforts to transfer a large outdoor cross in San Diego to the federal government must turn over some of their official records on the subject to a Jewish war veterans group challenging the Mt. Soledad memorial as an unconstitutional endorsement of religion, a federal judge ruled.

In an unusual 55-page opinion yesterday, Judge John Bates of the U.S. District Court for the District of Columbia rejected claims from the lawmakers, Brian Bilbray, Duncan Hunter, and Darrell Issa, that their files were protected from disclosure by the Speech and Debate Clause of the Constitution, which states that legislators “shall not be questioned in any other place” about legislative activities.

Judge Bates said that by sponsoring a bill to federalize the cross, Messrs. Bilbray, Hunter, and Issa opened themselves up to the demand for records. “These members in particular had every reason to suspect that their words and deeds as the Act’s sponsors would be the subject of post-enactment scrutiny; they played a high-profile role in the federal government’s acquisition of a large Latin cross that had been the subject of extensive prior litigation, made numerous public statements, and boasted of their role in campaign literature,” the judge wrote. “This Court’s case-specific ruling allowing discovery from these three Members neither works an injustice to them nor opens a proverbial can of worms for legislators generally.” Judge Bates’s ruling was something of a split decision. He said the legislators were entitled to withhold records pertaining to “legislative acts” but had to disclose records about attempts they made to convince executive branch officials to seize the land by public domain. The judge also said records of contacts with local officials, citizens’ groups, and the press might constitute “political activities” that are not protected from subpoena.

Although Judge Bates acknowledged that the distinctions were “not the brightest of lines,” he said the congressmen should make the first attempt to segregate the information.

The judge said respect for the independence of the legislative branch required that he become involved in assessing the documents only as a “last resort.”

The Mt. Soledad cross, which was erected in its current form in 1954, has since 1989 been the subject of a complex legal battle involving state and federal courts and three local referenda. Several courts, including the 9th Circuit Court of Appeals, have backed challenges to the memorial on church-state separation grounds. However, the cross has remained in place.

The Jewish War Veterans of America filed its lawsuit in San Diego last year after President Bush signed legislation seizing the land. To prevail, the group will have to prove that the legislation was intended to advance a religious goal. The dispute over the congressmen’s records was heard in Washington because that is where the files are located.

A lawyer for the Jewish group, Jonathan Siegelbaum, said yesterday that he was “grateful” for the judge’s ruling. “We believe the documents he ordered the members to produce will allow us to present a more complete picture of why the federal government’s actions are unconstitutional,” Mr. Siegelbaum said

Messrs. Bilbray, Hunter, and Issa are Republicans from the San Diego area. An attorney for the lawmakers, Kerry Kircher, did not respond to messages seeking comment for this article.