D.C. Court of Appeals Judge Frank Q. Nebeker, in an unusual display of anger in the courtroom, walked off the bench in the midst of a hearing yesterday after objecting to the tone of questioning under way by Chief Judge Theodore R. Newman Jr.

Personal and philosophical differences have long existed among the nine appeals court judges, but yesterday's incident was an unprecedented public demonstration of acrimony, according to court officials.

"I've never seen anything like it in 10 years of practicing appellate law," said attorney David A. Levitt, who was arguing before the three-judge panel on behalf of Samuel Moore, 27, a Southeast Washington man convicted last year of carrying an unregistered firearm and ammunition. "I felt this public display of lack of collegiality diminished the stature of the court."

During the hearing, Newman persistently asked assistant U.S. Attorney G. William Currier to answer a string of hypothetical questions about why the court should not suppress evidence gained against a suspect during a police search if the facts showed that the police had acted illegally in searching the suspect.

Newman's hypothetical case shared many characteristics with the Moore case. Moore's attorney, Levitt, had asked the appeals court to overturn Moore's firearms conviction on the grounds that Moore was the victim of an illegal police search.

Repeatedly Currier attemped to answer Newman's questions and repeatedly Newman interrupted Currier, by posing the same hypothetical questions in slightly different terms, according to the court record.

Suddenly, as Newman and Currier were still sparring, Nebeker rose from his seat and grumbled, "Farewell," according to witnesses who were in the courtroom.

"Prosecutors have a right to argue nonsense positions any way they want to, I guess," Newman said.

"I don't think we can be that pejorative about that," said Nebeker. "I can't allow my presence in here to indicate that I agree with that kind of conduct, Judge Newman," he added and, the witnesses said, walked out of the courtroom.

"You may proceed," Newman told Currier, and the hearing continued without Nebeker. "I was asking government counsel questions, seeking to probe what seemed to me to be an argument that was fallacious. I probed thoroughly as I often do. Apparently, one of my colleagues took exception," Newman told a reporter after the hearing.

Nebeker declined to comment on the incident. Judge William C. Pryor, the third judge presiding at the hearing, could not be reached for comment.

A rift between Nebeker and Newman came to light in 1980 when Nebeker and three other appeals court judges launched an extraordinary campaign to prevent Newman's reappointment as chief judge.

At that time Nebeker, who was Newman's chief opponent, told the D.C. Judicial Nominations Commission that he questioned whether it was "in the public interest" to reappoint Newman "when nearly overwhelming evidence shows his systematic injudiciousness, his deficiencies in temperament, his unilateral and unauthorized public pronouncements over court policy, (and) his predeliction for power rather than public service . . . ."

Newman declined at that time to comment on his colleagues' complaints, but his supporters contended that his critics were motivated by philosophical differences and questions of race. Newman is black, but the majority of appeals court judges are white. Newman's supporters also said the criticism was spurred by his efforts to improve court efficiency.