About 20 D.C. police officers angrily walked out of a press conference called yesterday by Police Chief Burtell M. Jefferson to announce that he was reinstating controversial Deputy Police Chief William Trussell.

The defiant walkout by the group of police union officials and homicide detectives under Trussell's command disrupted an already acrimonious news conference and reflected the bitter divisions in the department triggered by the four-month-long Trussell affair.

It was evident from the actions and comments of the police who crowded into the auditorium at headquarters for the chief's press conference that the controversy has brought to the surface longstanding but muted facial antagonisms in the department and has pitted rank-and-file police against their superior officers over lines of authority.

Jefferson stood quietly as television cameras turned from him to focus on the protesting officers. Later, he said, "They had a right to walk out just as they had a right to walk in."

The "white shirts," lieutenants and higher ranking officers, applauded that remark vigorously.

Later, the head of an association of black police officers in the department issued a statement in support of Jefferson, saying the Trussell controversy had been created by the white leadership of the police union in an effort to hurt Jefferson. He called on black officers to resign from the union.

Jefferson had temporarily removed Trussell, who is white, from command of the department's investigative units last May while a three-member panel appointed by Jefferson investigated charges by homicide detectives that Trussell was incompetent and had made a racially derogatory remark.

The chief said yesterday that he was reinstating Trussell because the panel had cleared Trussell of the charges. Jefferson also said he would transfer homicide Capt. Arif Mosrie because Mosrie had failed to handle the Trussell controversy properly.

"They (the panel) found the deputy to be competent and . . . did not feel he had unduly interfered in any investigation," Jefferson said. He said the panel had found that Trussell had made an "an improprietous (sic) remark, not a racial slur."

Even though the panel members cleared him, they had recommended, by a vote of 2 to 1, against Trussell's reinstatement, saying his ability to lead the investigative division had been seriously damaged by the controversy.

Panel members Maurice Turner and Marty Tapscott, both of whom are black and assistant police chiefs, said in their report to Jefferson that the dispute and Trussell's stated intention to sue some detectives for libel made Trussell's "ability to regain effective control of the division . . . increasingly doubtful." Their report said his authority had been "greatly diminished."

Panel member Richard Brooks, who is white and is an attorney for the police department, dissented, saying it would be "wholly contradictory" to clear Trussell of the charges and then remove him from command. Such an action would "indelibly shadow and taint" Trussell, Brooks said.

Brooks said the homicide detectives had "contrived" their account of a racial slur allegedly made by Trussell.

The detectives had accused Trussell of making a remark that equated blacks with animals. Turner and Tapscott determined in their report that Trussell had made the remark. They said it was "improprietous" but not a reason in itself to remove him from command.

Brooks said he believed that the allegations had been "contrived" and that detectives interviewed during the panel's investigation were not unanimous in their accounts of what had been said.

At his press conference yesterday, Jefferson said, "I have no alternative but to reassign Deputy Chief Trussell, I have the utmost confidence he is a professional police officer of 30 years of outstanding and creditable service to this department. For me to do otherwide, I could not justify it."

But, near the end of his statement, Jefferson said of the long and bitter controversy, "Everyone is a loser ... this department is a loser ... the entire city is a loser."

Homicide detectives appeared most angered yesterday by Jefferson's announcement that he would soon reassign Mosrie, the head of homicide, because Mosrie failed to head off his squad's criticisms.

That brought the walkout by the detectives.

Mosrie attempted to question Jefferson in front of reporters, but Jefferson ignored him, snapping to a newsman, "Capt. Mosrie knows the correct procedure (chain of command)." Jefferson then left the room.

Mosrie made a brief statement demanding a public hearing on his transfer, but was ordered to report to Jefferson's office before he could answer questions. Mosrie met with Jefferson for nearly an hour and declined to comment afterward. Friends said he is determined not to be made a "scapegoat" in the controversy.

Last May, Mosrie initially tried to defuse the squad's complaints against Trussell but later backed his squad before the panel.

"This (Mosrie) transfer is punitive, no doubt about it. He's being made the scapegoat and we're not accepting it," one detective declared. The detectives scheduled a meeting for Wednesday to decide their next move. Jefferson declined to discuss Mosrie's new assignment with reporters.

The third-floor hallway at police headquarters after the news conference was filled with small groups of officers expressing a variety of opinions about the splintering effect on the department of the series of events.

"everybody came down here looking for a soapbox," one officer said. Another commented, "There's nothing to this but who's going to lead . . . the officers or the men."

While arguments about chains of command dominated the conversations, the issue of black-white race relations also troubled officers.

". . . The Trussell racial thing was just being used by the white detectives as a lever," a black official commented.

Homicide squad detectives, black and white, denied it, although many black officials in other divisions have expressed similar feelings.

"The chief of police is trying to make this racial to keep his job," a detective said, "I wouldn't say we're all liberals in here, but we aren't racist."

Ronald Hampton, head of the D.C. Afro-American Police Officers Association, called on black officers to quit the International Brotherhood of Police Officers because its predominantly white board of directors had severely criticized Jefferson.

IBPO President Larry Simons, who is white, has called on the City Council to investigate Jefferson's handling of the Trussell affair, and has called for a "no-confidence" vote against Jefferson.

The union has a 62 percent minority membership, Simons said, including blacks and women as minorities. The police department itself has 1,840 black officers and 2,218 whites.

The Trussell controversy had embroiled Jefferson in conflicts with Mayor Marion Barry who had been critical all along of the chief's handling of the issue.

Yesterday, Barry released a one-page, handwritten statement that said, "I stand behind the chief's decision. I hope that this matter is put to rest . . . "

Barry on Thursday, however, had indicated he did not agree with Jefferson's decision.

"On this issue, the chief had his way," Barry said then. "I was not saying let's do it, let's not do it. There are a lot of things in this government I'm not happy with."

Barry also said, "I have faith that the chief can live with his decision. If this doesn't solve the problem, I'll have to review my role."