A federal judge sharply criticized the State Department last week for not disclosing government reports on political violence in El Salvador.

At issue is whether the Immigration and Naturalization Service has a duty to inform every illegal Salvadoran refugee -- at the time of arrest -- of the right to apply for political asylum.

Attorneys for the plaintiffs in a class action suit, filed on behalf of Salvadoran refugees, say that they want the State Department to turn the reports over to the court. The documents bear such titles as "Report on Death Squads in El Salvador" and "Torture Update."

U.S. District Court Judge David V. Kenyon said, "It appears people don't want to give the court information on death-squad activities in El Salvador . . . . To be brutally frank, the State Department and the government are playing hardball here. The court says, okay, we can play hardball here."

Allen Hausman, assistant director of immigration litigation for the Justice Department, said in an interview that "some of those documents are privileged . . . . We're particularly concerned about cable traffic from the embassy in El Salvador to Washington, and memos prepared by the State Department that are based on those cables."

Hausman told Kenyon that the reports would have to be subpoenaed. He added that, by the time the subpoena could be issued, Secretary of State George P. Shultz would have declared the reports secret and invoked executive privilege to prevent their release.

The judge responded that he would then demand to see the documents in private. "When the secretary of state . . . finds them secret, I'm going to have the reports in chambers here. The court is going all the way on this thing."

Mark Rosenbaum, an American Civil Liberties Union attorney acting for the plaintiffs, said later, "One of the issues in this case is, what's going on in El Salvador? . . . Are they going back to Club Med, or are they going back to a situation that endangers their lives?" Rosenbaum contends that the State Department "has the documentation of death squads, and torture and military bombings of civilians. They are withholding those documents to protect their foreign policy."

Hausman said, "Everybody in this case has a political agenda. The ACLU is in this case because they're attacking the administration's foreign policy . . . . I am not here to defend the government of El Salvador . . . . This is not a case about foreign policy . . . . What we are concerned with here are the rights of aliens under American law."

The suit was filed in 1982. That year, Kenyon issued a preliminary injunction, ordering the INS to inform all Salvadorans who entered this country illegally and were captured that they have a right to request political asylum. The plaintiffs are asking that the temporary order be made permanent and are seeking improved conditions in detention centers.

Rosenbaum has said that the temporary order is being ignored by some immigration officials, who have advised Salvadorans not to apply for asylum.

The plaintiffs are presenting testimony from Salvadoran emigres about their treatment by the INS. Hausman said the government would present "conflicting testimony . . . from the people who did the arresting."