1983:

NOVEMBER

President Reagan nominates Joseph E. diGenova, right, to be the U.S. attorney for the District of Columbia. He is sworn in a month later.

1984:

JANUARY

Mayor Marion Barry testifies before a grand jury that he did not use or purchase cocaine. Prosecutors have obtained a taped conversation in which Karen K. Johnson, a city employee indicted that spring for cocaine dealing, says she sold cocaine to the mayor 20 to 30 times.

Lawrence G. Strickland Jr. pleads guilty to racketeering and conspiracy charges in connection with a major cocaine trafficking and money laundering ring. Thirteen other defendants are ultimately convicted as participants. Strickland is sentenced to two concurrent seven-year prison terms.

JUNE

Karen Johnson pleads guilty to conspiracy to sell cocaine to other individuals and to cocaine possession. She receives a four-month sentence.

AUGUST

Johnson is jailed for eight months on a contempt citation after she refuses to testify before the grand jury investigating the mayor.

Barry accuses diGenova's office of leaking uncorroborated evidence to embarrass him.

SEPTEMBER

Barry requests the appointment of a special prosecutor to investigate whether diGenova has leaked secret grand jury information. The Justice Department announces the following May that an internal inquiry found "no evidence whatsoever" that diGenova or his staff leaked information.

1985:

MARCH

Paul Thayer, former deputy defense secretary, and his stockbroker, Billy Bob Harris, plead guilty to obstruction of justice in connection with their efforts to thwart a Securities and Exchange Commission investigation of insider trading that netted them and their associates about $3 million in profits. Each is sentenced to four years in prison.

NOVEMBER

Cornell Jones, the reputed narcotics kingpin of Hanover Place NW, pleads guilty to a charge of conspiracy to distribute cocaine. He is sentenced to nine to 27 years in prison.

Mohammed Ali Hamadei, a suspected Lebanese terrorist, is charged in a sealed indictment in connection with the 1985 hijacking of a TWA airliner and the murder of a U.S. Navy diver who was aboard. West Germany later refused to extradite him.

DECEMBER

Ivanhoe Donaldson, former D.C. deputy mayor, pleads guilty to theft and cover-up charges in a scheme that netted him more than $190,000 in D.C. government funds. Donaldson, once the mayor's top aide, receives a seven-year prison term. DiGenova says the case exposed "raw corruption" in the Barry administration.

1986:

APRIL

Ronald J. Perholtz and Franklin W. Jackson, former high-ranking U.S. Postal Service officials, are convicted of operating a $2 billion bribery, kickback and fraud scheme involving Postal Service and Small Business Administration contracts. Perholtz is sentenced to 10 years in prison, and Jackson gets seven years.

Alexander Exum, 53, executive assistant and chief of marketing for the D.C. lottery board, pleads guilty to accepting $5,500 in payoffs and the use of a Honda car from a lottery board contractor. DiGenova later predicts further indictments and says "the days of wheeling, dealing and stealing in the D.C. government are over."

MAY

Peter A. Voss, former vice chairman of the U.S. Postal Service board of governors and cochairman of Ronald Reagan's 1980 Ohio campaign, pleads guilty to taking $30,000 in kickbacks for Postal Service contracts. John Gnau, another Reagan state campaign chairman, later pleads guilty to paying an illegal gratuity to Voss. Voss is sentenced to four years in prison, and Gnau gets three years.

JUNE

Jonathan Jay Pollard, a former civilian Navy counterintelligence analyst, pleads guilty to participating in an espionage conspiracy directed by Israeli officials. His wife, Anne Henderson-Pollard, pleads guilty to related offenses. Pollard is sentenced to life in prison without parole; his wife gets five years.

1987:

MARCH

Aviem (Avi) Sella, a senior Israeli Air Force commander, is indicted for allegedly recruiting and supervising Jonathan Jay Pollard, but he remains a fugitive.

Beniamino Centurino, a member of the Sicilian Mafia and the alleged leader of a group that sold cocaine out of pizza restaurants here, pleads guilty to drug and racketeering charges. Fourteen others plead guilty in federal court here or in Alexandria in the so-called Pizza Connection case. Centurino is sentenced to 12 years in prison.

APRIL

Steven F. Madeoy, a real estate speculator, and two of his relatives are convicted of racketeering, bribery and conspiracy in connection with improper FHA-insured mortgages. Nine others are convicted of felony charges. Madeoy is sentenced to 32 months to eight years in prison.

MAY

Eddie Adair, the central figure in a major heroin distribution ring supplied by Nigerian nationals, is convicted of drug conspiracy and racketeering and sentenced to 12 to 38 years in prison. Three Nigerians also receive prison terms.

Alphonse G. Hill, former D.C. deputy mayor, pleads guilty to charges of defrauding the city government and income tax evasion. He receives a sentence of six to 30 months in prison, later reduced to six to 24 months.

Federal authorities search homes and businesses of friends and associates of Barry. Subsequent news stories detail a wide-ranging federal probe of D.C. government contracting and allegations that Karen Johnson was paid hush money in return for not testifying before a grand jury in 1984.

JUNE

Barry files a lawsuit accusing diGenova of leaking details of the corruption probe and of "prosecutorial vindictiveness." DiGenova calls the lawsuit an "unbridled and unsubstantiated attack."

JULY

A federal judge throws out Barry's suit for lack of proof.

SEPTEMBER

DiGenova announces that his office will drop 300 to 400 drug cases because of allegations that 4th District police officers skimmed drugs and money from raids.