Peter Rient, a former Watergate prosecutor, and architect of the U.S. Justice Department's Principles of Federal Prosecution, died in Darien, CT on September 2, 2025 at the age of 87. The cause of death was heart disease.
Peter Frank Rient was born on March 17, 1938, in Moscow, Russia. His mother, Gertrude Rient Gangadharan, was a Czech linguist employed by the U.S. embassy there. His father, Mandakulatur Vishvanata Gangadharan, was an Indian engineer who, several months before Peter was born, was arrested for espionage by Stalin's secret police and executed. In the summer of 1941, mother and son escaped Moscow ahead of the German invasion and, after a 72-day journey across Russia via the Trans-Siberian Railway, the Pacific Ocean, and the United States, reached New York City. There, after the war ended, Peter's mother met and married Walter Mansfield, an attorney who had served in the Marine Corps and the OSS during the war and who went on to become a federal judge. Together with Mr. Mansfield and his son Matthew, Peter and his mother took up residence in Norwalk, CT where Peter's sister Trina was born, and soon after the family moved to New Canaan, CT.
Peter's education, which he later described, gratefully, as "the best available in the United States," took place at the New Canaan Country School, Phillips Exeter Academy in Exeter, NH, Harvard College (from which he graduated, as a member of Eliot House and the Class of 1960 and concentrating in Greek History, with an A.B. magna cum laude) and Harvard Law School (LL.B. 1963). He then joined a U.S. Army intelligence unit and spent most of his active duty studying Mandarin Chinese and training to become an interrogator of prisoners of war.
Peter began his professional career as a litigation associate with the New York law firm of Winthrop, Stimson, Putnam & Roberts. A few years later he was appointed an Assistant United States Attorney in the Southern District of New York. There he spent three years prosecuting criminal cases including one year as the office's Chief Appellate Attorney.
In 1972 Peter moved to Washington, DC, where he had been asked to join a small group of Department of Justice attorneys to revise and reform the entire federal criminal code. In May of 1973, as that process was coming to a conclusion, the Watergate scandal erupted and Archibald Cox was appointed Special Prosecutor. Peter was one of the first prosecutors chosen by Mr. Cox as he assembled the Special Prosecution Force. Peter was assigned to the team tasked with investigating and prosecuting the participants in the Watergate cover up. His duties included drafting the indictment of President Nixon's henchmen, transcribing White House tapes to assist the trial jury as it listened to the recordings, and preparing legal memoranda for submission to trial judge Sirica.
After returning to DOJ in 1976 as Senior Counsel in the office for Improvements in the Administration of Justice, Peter undertook a survey of prosecutorial policies and practices of all 96 U.S. attorneys’ offices. On the basis of that work, which revealed numerous disparities, he drafted the Principles of Federal Prosecution, to ensure the uniform exercise of prosecutorial discretion by attorneys for the government. The Principles were adopted by the Department in 1980 and continue to promote its reasoned exercise of prosecutorial discretion today.
In early 1988 Peter took early retirement from the government to devote himself full-time to his family. Then in 1990, at the urging of his good friend and former DOJ colleague Ron Gainer, the two founded a small law firm with the purpose of representing victims of fraud or other illegal activity. The firm operated on a shoestring with modest success for several years before winning a substantial recovery for patent infringement in a case brought by a small company against the U.S., whereupon the partners declared the venture successful and closed their doors.
A quiet man who preferred to avoid attention, eschewed social media, disdained smart phones, and loved dogs and hats, Peter was keenly aware of the many blessings he had received in life, and sought to express his gratitude by helping others less fortunate. As a recovering alcoholic he joined in the founding of the Westside Club, a haven for the recovery community in Georgetown; he was a regular and active participant in meetings there and elsewhere; and he acted as a guide to other men in their quest for sobriety. He died with more than 48 years of sobriety. Peter served for ten years on the board of directors of the condominium where he lived, including three years as board president. Farther afield, Peter traveled far and wide to help others: in this country he went to New Orleans and Mobile to help rebuild communities damaged by Hurricane Katrina and to Utah to volunteer as a teacher's assistant at a school for Navajo children; abroad, he volunteered his time and energies to assist schools and communities in India, Costa Rica, St. Lucia, and the Cook Islands.
Proud as he was of his professional and other achievements what Peter valued most were his family — his son Sprague, his daughter Nell, and their mother Gretchen Theobald — and the time and adventures they shared. Unhappily, his marriage to Gretchen ended in divorce as did an earlier marriage to Dewitt Smith and a subsequent marriage to Joyce Craig. Happily, he and Gretchen were able to maintain a close and respectful relationship until Peter's death. His children and their mother survive him, as do his sister Trina Bayles, his brother Matthew Mansfield, his daughter-in-law Dina Rient, his grandsons Michael, George, and Christian Rient, as well as several cousins in the Czech Republic and Austria.
At his wishes, Peter's body was cremated and the ashes will be spread upon the waters of southern Maryland, where he spent many happy hours with his family and friends on his sailboat "Tashmoo."
The family had a memorial gathering in Washington, DC in October 2025.
This obituary contains minor modifications to the obituary published by The Washington Post on September 14, 2025.
