James Vorenberg, 72, a top assistant to Watergate special prosecutor Archibald Cox who later weathered the deanship of Harvard Law School during disputes about racial imbalance among the faculty, died April 12 at Massachusetts General Hospital after a heart attack.

Despite a 14-year battle with Parkinson's disease, he had taught legal ethics at Harvard since the end of his eight-year tenure as dean in 1989.

Mr. Vorenberg, long a nationally known figure on defendant rights, was selected for the Watergate probe in May 1973 largely because he and Cox were peers at Harvard Law School and Mr. Vorenberg knew the maze of Washington bureaucracy.

He stayed on for two years as associate special prosecutor, assisting in a largely managerial capacity by hiring a stable of lawyers, while Cox did much of the investigative work on the 1972 Watergate break-in and other wrongdoings by President Richard M. Nixon, his staff and his supporters during that election year.

Cox said in an interview this week that Mr. Vorenberg also was an informal adviser on policy and legal judgment. Mr. Vorenberg stayed on part time after Nixon had Cox fired in the October 1973 "Saturday Night Massacre" in an effort to stem the investigation.

Mr. Vorenberg was more directly involved in the heat of controversy while serving as Harvard Law School dean. He was credited with addressing the concerns of black students, who felt there were too few minority faculty members. He helped establish a policy statement expressing commitment to diversity in hiring and the inclusion of students in hiring decisions.

He was a Boston native and a graduate of Harvard College. He received a law degree from Harvard in 1951 and was president of the Harvard Law Review. He served two years in the office of the Air Force general counsel, then clerked for U.S. Supreme Court Justice Felix Frankfurter from 1953 to 1954. He worked at a Boston law firm until joining the Harvard law faculty in 1962.

Later, he served on commissions reviewing bail and police interrogation procedures, the right to counsel and pretrial publicity. In 1964, he took leave from Harvard to be part-time director of the Justice Department's new Office of Criminal Justice.

In 1965, he became executive secretary of President Lyndon B. Johnson's Commission on Law Enforcement and Administration of Justice. In that job, he oversaw the creation of a code of procedural conduct covering the pretrial period, beginning with the moment someone is arrested.

The commission's report prompted federal grants of nearly $1 billion annually to state and local criminal justice agencies.

A witty man who loved experimenting in the kitchen, he wrote a cookbook in 1990 with Jack Greenberg, then vice dean of Columbia Law School. "Dean Cuisine: The Liberated Man's Guide to Fine Cooking" received a positive notice from Julia Child in the Harvard law Bulletin.

His marriage to Dorothy Greeley ended in divorce.

Survivors include his wife, Elizabeth Vorenberg of Cambridge, Mass.; three daughters from his first marriage, Jill Alberts of New York, Amy Vorenberg of Concord, N.H., and Eliza Vorenberg of Los Angeles; two stepchildren, Amy Troubh of Newton, Mass., and John Troubh of New York; and 10 grandchildren.