Undated photo of Bruce J. Terris, a public interest lawyer. (Family Photo)

Bruce J. Terris, a public interest lawyer for more than 50 years who during the 1960s and ’70s was an activist on legal issues and community organizing related to anti-poverty programs, died Feb. 3 at his home in Washington. He was 83.

The cause was cancer, said his wife, Sally Gillespie.

Since 1970, Mr. Terris had been a partner in a law firm he founded, now known as Terris Pravlik & Millian, specializing in environmental and employment cases.

Earlier, as a Justice Department lawyer, he played a pivotal role in the 1963 U.S. Supreme Court’s “one man, one vote” decision requiring that state legislatures be apportioned on the basis of population.

Mr. Terris advised Solicitor General Archibald Cox that the equal protection clause of the Constitution required that both houses of a legislature be apportioned on the basis of population, not just one, as had been previously argued. That position prevailed in the Supreme Court.

Later in the 1960s, Mr. Terris was executive director of the Anacostia Assistance Corp., a nonprofit organization that provided technical and financial help to organizations and low-income people in the District’s Anacostia neighborhood.

About that same time, he co-founded and was senior attorney of the Center for Law and Social Policy, which represented the poor and dispossessed on a variety of issues before federal agencies and the courts.

Bruce Jerome Terris was born in Detroit on Aug. 3, 1933. He graduated from Harvard University in 1954 and Harvard Law School in 1957.

In private practice, he represented groups including Friends of the Earth, the Sierra Club and consumer organizations and handled cases involving discrimination against women in the workplace, clear-cutting in national forests, misleading advertising for non-prescription drugs, and environmental pollution.

The firm took on many clients who could not pay and often collected fees only when they won their cases with a provision that the other side pay legal costs.

His first wife, the former Shirley Duval, died in 1976. Survivors include his wife of 39 years, Sally Gillespie of Washington; three children from his first marriage, Elizabeth Terris of San Diego, Jessica Kehimkar of Snohomish, Wash., and Robert Terris of Berkeley, Calif.; a stepdaughter, Sally Phillips of Washington; and 10 grandchildren.