For Richard Nixon, the fateful moment of his career probably arrived on the night of October 19, 1973, when a recently appointed Justice Department lawyer--a reticent and modest man with a tweedy professorial manner--decided to proceed with his Watergate inquiry in defiance of a direct presidential order.

That decision--calling Nixon's bluff on his bid to refuse evidence to the government prosecutors--backed the president against a wall. Cornered by incriminating disclosure on the one hand and public outrage over acts of non-compliance on the other, Nixon stands on the brink of disgrace.

That decision led the president to fire the Justice Department lawyer and oust his two superiors. It resulted in Nixon bowing to public pressure and releasing some of his subpoenaed tape recordings to the federal court. As a consequence of the firings, the House of Representatives began the first serious impeachment inquiry in more than a century.

The scenario reads like an excerpt from the "Profiles of Courage" that John F. Kennedy '40 once collected, complete with the David-and-Goliath theme that sentimentalist historians adore. But Archibald Cox '34, Williston Professor of Law, the special prosecutor who defied the most powerful man in the Western world, and hero to millions of Watergate-watchers, was an unlikely candidate for gallantry.

When then-Attorney General-designate Elliot L. Richardson '41 persuaded Cox to accept the special prosecutor position in May 1973. Cox was hardly a household name in America, and even at Harvard the soft-spoken labor lawyer was often overshadowed by his more outspoken colleagues.

Born in New Jersey when Woodrow Wilson was still governor, the 62-year-old Kennedy Democrat had attended St. Paul's, the College, and the Law School during the height of the Depression. A labor negotiator with a hard-nosed reputation, Cox served in the Solicitor General's Office under Roosevelt in the '40s and on the Wage Stabilization Board under Truman.

Cox resigned his post on the Wage Board in 1952--gaining his first public notice and boosting his reputation for independence--after Truman reversed his decision on a wage demand by the United Mine Workers.

Cox later served from 1961 to 1965 as solicitor general for both Presidents Kennedy and Johnson, demonstrating a diligent loyalty and developing a number of professional and social contacts with career officials in the Justice Department.

At Harvard, Cox was probably best known for his role as "University troubleshooter" near the end of the Pusey Administration. In the spring of 1968, Cox chaired a blue-ribbon fact-finding commission that studied the Columbia University student disorders of that year. In the fall of 1969, just after the University Hall bust, the Corporation granted him a broad mandate to handle disorders at Harvard.

In early March 1971, Cox almost single-handedly brought a non-violent end to a nine-day occupation by militant women of a vacant building at 888 Memorial Drive. Two weeks later, Cox earned notoriety among Harvard radicals for his part in the controversy surrounding the pro-war "counter teach-in."

Cox pleaded with students at the Sanders Theater meeting no to disrupt the speeches by representatives of the South Vietnamese and other governments. Cox later headed the inquest which led to CRR trials for a number of students who took part in the chanting and clapping that disrupted the teach-in.

Throughout his career, the trim, tall Cox, with his close-cropped gray hair and half-moon glasses, had steered an independent if unexceptional course. But, as The New York Times commented the week he was fired, "Before, few had thought of Archibald Cox as salty."

President Nixon, with all the swollen powers of the Executive Branch behind him, evidently saw no salt whatever in Archie Cox. When the president refused a Circuit Court order to hand over nine tapes to Judge John J. Sirica and ordered Cox "to make no further attempts by judicial process to obtain the tapes," he expected Cox would quietly resign as he had when Truman crossed him.

Cox must have known on October 19 when he received Nixon's order that his job was finished regardless of which course he chose. If he obeyed he would never obtain the evidence for a successful prosecution. If he defied the president's fiat, he would surely be fired.

At the news conference the next morning when he announced his intention to continue in pursuit of the tapes, Cox spoke quietly but firmly. "For me to comply to those instructions would violate my solemn pledge to the Senate and the country to invoke judicial process to challenge exaggerated claims of executive privilege. I shall not violate my promise," he said.

In the heat of a grave political crisis, a modest man became momentarily a heroic one. Now, eight months later, Cox has returned to his book-lined office in the International Legal Studies Building at the Law School, saying little about the scandal even in his now-frequent speeches and waiting modestly for the other shoe, the one his defiance set in motion, to drop on Richard Nixon.