BOSTON -- Former police captain Gerald W. Clemente was sentenced yesterday to 15 years in prison for orchestrating a scheme to steal, sell and alter tests given police officers seeking promotion.

Clemente, who became the government's star witness against exam cheaters, got a stinging reprimand from U.S. District Court Judge William G. Young, along with the sentence.

"You are one of the most amoral, arrogant and manipulative individuals to ever appear before the court," Young said.

Three other former police officers were given prison sentences, joining five other defendants who were given prison terms last week. One was Clemente's brother, Robert, a former police lieutenant who received four years.

Clemente, who was fined the maximum $25,000 for his convictions on racketeering, conspiracy and other charges, will begin his federal sentence after completing a 30- to 40-year sentence he received for his part in the 1980 bank burglary at Depositor's Trust in Medford.

Officials have said the careers of more than 100 officers may have been stalled because of promotions given to officers who cheated on exams. About 75 officers from several departments plan to file a class-action suit seeking promotions and back pay, according to an attorney preparing the suit.