As an obscure but muscular congressional staffer and chairman of the Federal Trade Commission, he helped usher into law a raft of consumer protections.Few people outside Washington had ever heard of the consumer advocate Michael Pertschuk by the mid-1970s, but he was considered so influential in Congress that friends and foes alike anointed him “the 101st senator,” and the cigarette maker Philip Morris proclaimed him the company’s “number one enemy.”While he never held elective public office, Mr. Pertschuk occupied, as The Washington Post wrote in 1977, “the top stratum of an invisible network of staff power and influence in the Senate, with impact on the life of every citizen of the United States.”Probably more than any other individual, he was responsible for the government’s placing warning labels on cigarettes, banning tobacco advertising from television and radio, requiring seatbelts in cars and putting in place other consumer protections — all by helping to draft those measures into law as the chief counsel and staff director of the Senate Commerce Committee and later as the chairman of the Federal Trade Commission under President Jimmy Carter.“I spent a good part of my life making life miserable for the tobacco companies,” Mr. Pertschuk had said, “and I’m not sorry about that.”He died on Nov. 16 at his home in Santa Fe, N.M. He was 89. His wife, Anna Sofaer, said the cause was complications of pneumonia.Mr. Pertschuk, second from right in the foreground, and other appointees take the oath of office in a White House ceremony in April 1977. He was named F.T.C. chairman. His wife, Anna Sofaer, is at right. Justice William J. Brennan of the Supreme Court administered the oath, with President Jimmy Carter flanking him. Associated PressFor ordinary consumers who were vexed by the government’s lax oversight of the tobacco and auto industries beginning in the mid-1960s, Mr. Pertschuk was their unseen legal guardian.He helped draft the Natural Gas Pipeline Safety Act, the Recreational Boat Safety Act, the Federal Railroad Safety Act, the Consumer Product Safety Act, the Toxic Substances Act and the Safe Drinking Water Act. Decades later, he lifted the veil on government sausage-making in his book “When the Senate Worked for Us: The Invisible Role of Staffers in Countering Corporate Lobbies” (2017).“Few have done more to reduce tobacco use in the United States and to galvanize and empower the tobacco control movement than Mike Pertschuk,” Matthew L. Myers, the president of the Campaign for Tobacco-Free Kids, said in a statement.He added, “He arguably became the most aggressive Federal Trade Commission chair in history and pursued powerful preventive health measures, including a proposed ban on advertising targeted at children.”The consumer advocate Ralph Nader, with whom Mr. Pertschuk collaborated closely on auto safety and other issues, described him as “a brilliant strategist, organizer and human relations genius while he was reshaping the Commerce Committee into the ‘Grand Central Station’ of consumer protection.”“He also ignited the anti-tobacco industry movement on Capitol Hill and later traveled the world motivating other countries to do the same,” Mr. Nader said in a statement.Mr. Pertschuck in 1984. He remained an F.T.C. commissioner after Ronald Reagan became president. Stepping down, he said the administration’s “ideological blindness led to a new era of regulatory nihilism and just plain nuttiness.” George Tames/The New York TimesMichael Pertschuk was born on Jan. 12, 1933, in London to a Jewish family who had sold furs in Europe for generations but who fled in 1937 as Nazi Germany codified anti-Semitism and girded for war. His father, David, opened a fur store in Manhattan. His mother, Sarah (Baumgarten) Pertschuk, was a homemaker.He graduated from Woodmere Academy on Long Island, where he grew up, earned a bachelor’s degree in literature from Yale in 1954, served in an Army artillery unit from 1954 to 1956 and was discharged as a first lieutenant. He received his law degree from Yale Law School in 1959.After clerking for Chief Judge Gus J. Solomon of the U.S. District Court in Oregon, he was hired in Washington in 1964 as a legislative assistant to Senator Maurine B. Neuberger, an Oregon Democrat. About the same time, the United States surgeon general released his groundbreaking report linking smoking to cancer and probably heart disease, and a year later Mr. Nader published his book “Unsafe at Any Speed,” which labeled the compact Chevrolet Corvair, with its engine mounted in the rear, as a “One-Car Accident.” Emerging as the Senate’s leading staff expert on tobacco control legislation, Mr. Pertschuk was recruited by Senator Warren G. Magnuson, the Oregon Democrat who was chairman of the Commerce Committee. Mr. Pertschuk served as a counsel to the committee from 1964 to 1968 and as chief counsel and staff director from 1968 to 1977, when he was named chairman of the Federal Trade Commission.He relinquished the chairmanship after Ronald Reagan was elected president in 1980 but remained a commissioner until 1984. During his tenure he forced the funeral industry to itemize its charges, but as the climate for regulation cooled, he failed in his effort to ban TV commercials aimed at marketing sugary foods to children.On leaving office, Mr. Pertschuk blamed the Republican administration for fostering de-regulaton, he said, whose “extremism and ideological blindness led to a new era of regulatory nihilism and just plain nuttiness.”Mr. Pertschuk’s first marriage, in 1954, to Carleen Joyce Dooley, ended in divorce in 1976. He married Anna Phillips Sofaer in 1977.In addition to his wife, he is survived by two children from his first marriage, Amy and Mark Pertschuk; a stepson, Daniel Sofaer; and three grandchildren.He and his wife moved from Washington to Santa Fe in 2003.Asked what motivated Mr. Pertschuk to embark on his consumer crusade, Joan Claybrook, who headed another of his progenies, the National Highway Traffic Safety Administration, during the Carter administration, said in a phone interview: “The facts. The more he learned, the more adamant he became. The more he learned about tobacco, the more outraged he became and the more determined he was to do something about it. And he was in a position of enormous power to do something about it.”After leaving government, Mr. Pertschuk founded, with David Cohen, a former president of Common Cause, the Advocacy Institute, which trained social justice adherents in the United States and emerging democracies.Mr. Pertschuk explained why he hadn’t capitalized on his enormous congressional and commission experience by going to work for a law firm, or for corporate clients or for foreign governments.“There is a career to be made out of the craft of lobbying for things you believe in,” he told The New York Times in 1987. “You may lag behind your contemporaries in BMW’s, if not Cuisinarts, but it really is worth it.”“This is more fun,” he said. More