Former Secretary of the District David E. Rivers, once considered part of Mayor Marion Barry's inner circle, has been secretly named by federal prosecutors as an alleged co-conspirator who used cocaine with Barry, according to sources familiar with Barry's drug and perjury case.

Witnesses have told law enforcement authorities that Rivers, the highest-ranking current or former government official yet to be named in the case other than Barry, used cocaine on several occasions with Barry, according to sources.

Rivers and his lawyer, Francis Carter, said yesterday they were not cooperating with or providing information to either defense lawyers or prosecutors in the Barry case. They also said they had not been contacted by either side about being a potential witness.

"We are completely in the dark," Carter said. "I don't know what's going on," Rivers said. "I have absolutely no idea."

Rivers is one of 19 people identified by prosecutors as unindicted co-conspirators in the Barry case. The legal identification of Rivers as a co-conspirator will allow prosecutors to introduce statements made by Rivers to other witnesses about alleged drug use by Barry without calling Rivers to the stand.

Rivers's name has been closely held. On May 27, The Washington Post was able to confirm the identity of 16 of the 19 people on the co-conspirators' list. Rivers was not among them, nor was he named as a potential witness in a separate list of 48 possible prosecution and defense witnesses released Monday.

The absence of Rivers's name from the prosecutors' prospective witness list apparently prompted defense lawyer R. Kenneth Mundy to identify Rivers yesterday as a possible defense witness in a separate list given to Judge Thomas Penfield Jackson. According to a source, Mundy thought it was necessary to discover if any of the prospective jurors had any knowledge or feelings about Rivers in case his name were to come up in the trial.

Rivers is on trial along with city businessman John Clyburn on bribery and conspiracy charges on the sixth floor of the U.S. District Courthouse, four floors above the site of the Barry trial. Rivers and Clyburn are accused of steering more than $2 million worth of city contracts to Clyburn and his associates.

Rivers has not been charged with any drug-related offenses, but traces of cocaine were found in his home in May 1987 when FBI agents executed a search warrant there.

In secretly recorded conversations played to the jury in the Rivers and Clyburn case, Clyburn -- also a close friend of Barry's -- discussed Rivers's and Barry's close friendship. It could not be determined yesterday how many of the alleged co-conspirators would testify as witnesses in the Barry case.

In the list he gave to the judge yesterday, Mundy included co-conspirators not identified by prosecutors as potential witnesses.

This does not mean they will testify as defense witnesses, but rather could be a defense strategy designed to pinpoint prospective jurors who may know something about those named. Included in Mundy's new list were alleged co-conspirators Daniel Butler, a close Barry friend, and Gaylord Tissueboo, former Barry photographer.

Other possible witnesses include Arthur Jeffrey Mitchell, an advertising executive; Lloyd N. Moore Jr., a lawyer; and Darrel Sabbs, a former city government employee. All three have been named as co-conspirators and have agreed to cooperate with prosecutors, sources said.

Also named by Mundy were Anita Bonds, the mayor's chief political operative, and Willie Davis, a former aide to Birmingham Mayor Richard Arrington and close Barry friend.

Mundy did not want to reveal Rivers's name in open court yesterday, telling the judge that there was one prospective witness whose name should be kept secret. But after a discussion at the bench, Jackson publicly disclosed Rivers's name.

Among the 48 names disclosed to prospective jurors on Monday were those of former Barry girlfriends, former city employees and local business figures.

Perhaps the best known people on the list were former D.C. employee Charles Lewis and former model and Barry girlfriend Hazel Diane "Rasheeda" Moore.

Lewis pleaded guilty to perjury and conspiracy charges last year and told prosecutors that he used cocaine with Barry at the Ramada Inn in downtown Washington and in the Virgin Islands.

U.S. Attorney Jay B. Stephens has said the case against Barry started with the Ramada episode and that Lewis's decision to cooperate was a turning point in the investigation.

Another possible witness, James D. McWilliams, has pleaded guilty to aiding and abetting Lewis's possession of cocaine at the Ramada and is expected to corroborate portions of Lewis's testimony about smoking crack with Barry.

Moore was the FBI informant who invited Barry to the Vista Hotel in January, where he was videotaped allegedly smoking crack cocaine. In addition to Moore, her mother, Mary Moore; her sister, Mertine Moore; and her sister-in-law, Sherle Moore, have been listed as possible witnesses.

The list also includes two current members of Barry's security detail, Detectives James Stays and Fred Gaskins. Both officers are expected to testify about the Ramada episode, sources said. Additionally, the list includes the name of Ronald Harvey, a former supervisor of the security detail.

Four of the possible witnesses -- Dixie Hedrington, Zenna Matthias, Albert Benjamin and Linda Maynard -- are expected to testify about Barry's alleged drug use during trips to the Virgin Islands in 1986 and 1988, sources said.

Two of the witnesses, Georgetown restaurateur Hassan H. Mohammadi and Sammad Arshadi, are expected to testify that they have provided drugs to the mayor, sources said. Mohammadi pleaded guilty last month to conspiring to possess cocaine as part of a plea agreement with federal prosecutors. That agreement was filed under seal, sources said.

Additionally, a source familiar with the case identified Charles Mason as an alleged co-conspirator in the case. Mason, a special assistant in the Department of Public Works since 1984, declined to comment yesterday. Mason was on the list of possible witnesses distributed Monday.

According to sources, several people on the witness list are close friends of Barry's who may testify about the mayor's alleged drug use.

They include Theresa Southerland, Doris Crenshaw, Johnann Coleman, Bettye Smith, Rose Maria McCarthy, Carole Bland Jackson, Marcia Griffin and Wanda Stansbury. Additionally, the list includes the name of Tivia Hoppenstein, a close friend of Barry associate and real estate developer R. Donahue Peebles.

Albert Arrington

Sammad Arshadi

Maandria Askia

Maria Barba

Albert Benjamin

Orlando Berrios

Anita Bonds

Daniel Butler

Johnann Coleman

Doris Crenshaw

Carthur Drake

Willie Davis

Fred Gaskins

Marcia Griffin

Ronald Harvey

Dixie Hedrington

Tivia Hoppenstein

Carole Jackson

Wanda King

Charles Lewis

Thomas Lynch

Roger Martz

Charles Mason

Zenna Matthias

Linda Maynard

Rose M. McCarthy

James McWilliams

David Meyerson

Arthur Jeffrey Mitchell

Hassan H. Mohammadi

Lloyd N. Moore Jr.

Mary Moore

Mertine Moore

Rasheeda Moore

Sherle Moore

John Olsen

James Pawlik

Lydia Pearson

Edward Prichard

Marshall Reel

Robin Ridgeway

David Rivers

Darrel Sabbs

Sukhjit Singh

Roy Schneider

Bettye L. Smith

Theresa Southerland

Wanda Stansbury

James Stays

Frank Steele

Gaylord Tissueboo

Jonetta Vincent

Clifton West

Peter Wubbenhorst