The judge presiding over the perjury trial of former White House aide Michael K. Deaver yesterday threatened to halt the three-day-old proceeding after a federal appeals court directed him to cease questioning all potential jurors in private.

U.S. District Court Judge Thomas Penfield Jackson said the ruling had so seriously eroded his credibility with the jury panel that he had "very grave doubts" if the case against the longtime confidant to President and Mrs. Reagan could proceed. "I frankly find myself embarrassed to face this panel again," the judge said.

His comments were made minutes after the Court of Appeals of the District of Columbia responded to an appeal by major news organizations by rejecting Jackson's procedure of questioning the potential jurors away from the press and the public.

A three-judge panel of the appeals court said that Jackson's procedures flew in the face of a judicial tradition dating to England that requires criminal proceedings, including jury selections, be conducted in open court.

Lawyers for Deaver, a Washington lobbyist accused of lying to a congressional subcommittee and grand jury about his post-White House contacts with high government officials, and his prosecutor expressed alarm at the prospect of delaying the trial.

That, said independent counsel Whitney North Seymour Jr., the prosecution lawyer, would be "a disaster."

"I concur," Jackson said. But he said it would be a "bigger disaster" to allow the case to continue with a jury that has been incorrectly selected.

When Seymour and Herbert Miller Jr., Deaver's lawyer, urged that the judge resume questioning potential jurors from the same panel, Jackson appeared reluctant, citing the ruling as "definitely, irrevocably" destroying his authority with the jury panel.

"We can't afford this," Miller said after the hearing. Asked why, he replied: "Because we are not made out of money."

Jackson said he understood that the costs of a delay would be substantial and that summoning a new panel of 100 potential jurors would take about three weeks. He is to announce his decision on proceeding or delaying the trial today.

Once in Jackson's courtroom, the 100 original jurors who had been summoned were asked a few general questions en masse and then handed a 12-page document containing questions the judge said were sensitive and personal.

Some dealt with the jurors' experience with alcoholism and drug abuse, issues that are important in the Deaver trial because the defendant may argue that excessive drinking and his abuse of prescription drugs impaired his memory of the events in question.

After the jurors completed the form, the judge and the lawyers began questioning them individually in the jury room. Lawyers for news organizations, including the four television networks, The New York Times and The Washington Post, protested the practice, saying it was inconsistent with a 1984 Supreme Court ruling requiring open jury selection.

Yesterday morning those arguments went before the appeals court panel, sitting three floors above Jackson's court. There Seymour asserted that the news media were not seeking "access to public information; it's to watch them {the potential jurors} squirm."

"You don't think that the First Amendment covers what you say is 'watching the jurors squirm'?" said Laurence H. Silberman, one of the three judges.

Judge Kenneth W. Starr cited a tradition of openness in the United States and England that may require "that jurors may have to squirm" in public when questioned.

Seymour, a Park Avenue lawyer appointed by the courts to investigate Deaver's lobbying business, said during the arguments that the closed proceedings were especially helpful because many on the jury panel had difficulty filling out the questionnaire.

"These are reasonably unlettered people, mostly verbal," he said. "To ask them to fill out a questionnaire to state their reasons would almost be a joke."

Jackson said the appeals court opinion did not spell out that he should continue the trial.

"They didn't make that clear in the opinion, which is the ruling to which I must conform," he told the lawyers. "I'm afraid I've given so many conflicting instructions to the jury panel that I don't think another set of instructions will do any good," he said. "The larger question is the erosion of authority of a trial judge. With this panel, my authority has been definitely, irrevocably been eroded . . . . "