While serving as US Deputy Attorney General in October 1973, in what became known as the "Saturday Night Massacre,"[2] Ruckelshaus and US Attorney General Elliot Richardson resigned from their positions rather than obey the order of US President Richard Nixon to fire the independent special prosecutor, Archibald Cox, who was tasked with investigating Nixon's role in the Watergate scandal.

[4] He began college at Princeton University before being drafted[6] and serving for two years in the United States Army, becoming a drill sergeant at Fort Lewis in Tacoma, Washington.

[11] In 1964, Ruckelshaus ran as a moderate Republican in the U.S. House election in Indiana's 11th district, losing in the primary to Don Tabbert, a candidate from the conservative wing of the party.

Although many people were mentioned as possibilities for the new position, the choice of Ruckelshaus had been based upon the strong recommendation of US Attorney General John N. Mitchell.

The Justice Department under Mitchell filed a civil lawsuit against the Jones and Laughlin Steel Company "for discharging substantial quantities of cyanide into the Cuyahoga" at Ruckelshaus's request and sought an injunction "to halt the discharge of these deleterious materials into the river...."[4][17] Also during his first tenure at the EPA, Ruckelshaus advocated for and enacted a ban on the insecticide DDT.

[4] Ruckelshaus laid the foundation for the EPA by hiring its leaders by defining its mission, deciding on priorities, and selecting an organizational structure.

[18][19] In April 1973, during the growing Watergate scandal, there was a major reshuffling of Nixon administration posts because of the resignations of White House Chief of Staff H. R. Haldeman and Domestic Affairs Advisor John Ehrlichman.

Ruckelshaus's record of success at EPA and Justice and his reputation for integrity led to his being appointed acting Director of the Federal Bureau of Investigation to replace L. Patrick Gray III, "who had allowed Nixon aides to examine Watergate files and had even destroyed evidence in the case.

[20] After the resignations, the third in command at the Justice Department, US Solicitor General Robert Bork immediately effected the firing and the abolition of the special prosecutor's office, completing the "Massacre."

[21] In 1975, Ruckelshaus moved to Seattle, Washington, where he accepted a position as senior vice-president for law and corporate affairs of the Tacoma-based Weyerhaeuser timber company.

Ford selected Bob Dole; the two lost the election to Democrat Jimmy Carter and his running mate, Walter Mondale.

[26] Ruckelshaus attempted to win back public confidence in the EPA, a challenging task in the face of a skeptical press and a wary Congress, both of whom scrutinized all aspects of the agency's activities and some of whom interpreted a number of its actions in the worst possible light.

[4][6] On November 28, 1984, Ruckelshaus announced that he would be retiring as EPA head, effective January 5, 1985, around the start of President Reagan's second term.

[25] Of his two tenures at EPA, Ruckelshaus later reflected:[27] I've had an awful lot of jobs in my lifetime, and in moving from one to another, have had the opportunity to think about what makes them worthwhile.

As the company expanded its operations into New York City, Ruckelshaus "helped investigators infiltrate a Mafia-dominated carting conspiracy, leading prosecutors to obtain indictments.

[30] Ruckelshaus served as a director on boards of several corporations, including Isilon Systems, Monsanto, Cummins, Pharmacia, Solutia, Coinstar, Nordstrom, Pfizer, and Weyerhaeuser.

[35] In August 2016, Ruckelshaus and another former Republican-appointed EPA administrator, William K. Reilly, jointly endorsed Hillary Clinton for president in the 2016 election.