Henry S. Ruth, Who Helped Lead Watergate Prosecution, Dies at 80 Henry S. Ruth Jr., who helped lead the criminal prosecution of Nixon administration officials involved in covering up the Watergate break-in and kept it on track when President Richard M. Nixon fired the special prosecutor Archibald Cox, died on March 16 in Tucson. He was 80. The cause was a stroke, his wife, Deborah Mathieu, said. Mr. Ruth had broad experience in criminal law when he became Mr. Cox's chief deputy shortly after Mr. Cox's appointment as special prosecutor in May 1973. Five months later, on Oct. 20, President Nixon ordered Mr. Cox's dismissal after he refused to drop his plan to subpoena tapes of the president's conversations in the Oval Office. The firing prompted the two top Justice Department officials, Attorney General Elliot Richardson and his deputy, William Ruckelshaus, to quit in what became known as the Saturday Night Massacre. The case concerned the possible involvement of Nixon and his aides in covering up the June 1972 break-in at the Democratic national headquarters in the Watergate apartment complex by burglars who turned out to have ties to Nixon's re-election campaign. A Nixon aide, Alexander P. Butterfield, had revealed the existence of the secret tapes to a Senate investigative committee in July 1973. In the upheaval that followed Mr. Cox's dismissal - when it was not known whether the special prosecutor's office would continue and, if it did, what powers it might have - Mr. Ruth was credited with holding the office together. He gathered the distraught staff around him and persuaded them to stay on and preserve the evidence, The New York Times reported. On Nov. 1, Leon Jaworski, a prominent lawyer from Texas, became special prosecutor. Asking Mr. Ruth to remain as his deputy was his first piece of business, Mr. Jaworski wrote in "The Right and the Power: The Prosecution of Watergate" (1976). "He is a slender, mild-mannered man, so unassuming that some people, on first meeting, were inclined to misjudge his talents," Mr. Jaworski wrote of Mr. Ruth. In "The Final Days" (1976), Bob Woodward and Carl Bernstein wrote that Mr. Ruth had met privately with Leonard Garment, Nixon's special counsel, to ask if Mr. Garment could persuade the president to resign. Mr. Garment said he had already tried and failed. Under Mr. Jaworski, the prosecutors persuaded the Supreme Court to order that the tapes be turned over to prosecutors, and the top Nixon aides H. R. Haldeman, John Ehrlichman, Charles Colson and John N. Mitchell, the former attorney general, were either convicted or pleaded guilty. As evidence mounted and the House of Representatives prepared articles of impeachment against the president, Nixon resigned on Aug. 8, 1974. President Gerald R. Ford issued a blanket pardon of Nixon the next month. When Mr. Jaworski stepped down two months later, he urged that Mr. Ruth replace him. Mr. Ruth's first act was to challenge part of the pardon deal that restricted his access to tapes. He won: the special prosecutor was given full access. Mr. Ruth was special prosecutor until October 1975, when he issued a 277-page report on the Watergate investigation. It said prosecutors had thus far convicted or obtained guilty pleas from 55 individuals and 20 corporations. They had been unable to determine who was responsible for erasing 18 1/2 minutes of a Nixon tape that many thought might have been incriminating, the report said, even though "a very small number of people could have been responsible." The report disclosed that prosecutors had explored whether Ford's pardon amounted to illegal interference with the mandate of the special prosecutor. But both Mr. Jaworski and Mr. Ruth concluded that the president's power to pardon was stronger than the mandate. Charles F. Ruff succeeded Mr. Ruth as the fourth and last special Watergate prosecutor. Henry Swartley Ruth Jr. was born in Philadelphia on April 16, 1931; graduated from Yale and the University of Pennsylvania Law School; served two years in the Army; and worked as a private lawyer. He was a special attorney under Attorney General Robert F. Kennedy. After teaching law at Penn for two years, he returned to the Justice Department in its research arm, the National Institute of Law Enforcement and Criminal Justice. A year later, he became criminal justice coordinator for New York City under Mayor John V. Lindsay. Mr. Ruth's first marriage, to Christine Polk, ended in divorce. In addition to his wife, Ms. Mathieu, he is survived by his daughters, Deborah, Diana and Tenley Ruth, and three grandsons. After his Watergate work, Mr. Ruth worked mainly in private practice. John Dean, a Nixon aide, wrote in his book "Blind Ambition: The White House Years" (1976) that he once asked Mr. Ruth what he planned to do in the future. Mr. Ruth replied that he might do American Express commercials, of the sort that made fun of forgotten celebrities who had fallen from the limelight. "You may not remember me, but I'm the Watergate special prosecutor," he said, holding up a credit card, as if he were in a commercial. "I used American Express all through Watergate, because nobody knew who I was," he continued. And they still don't know who I am.