Marvin Wulf, a constitutional lawyer who reshaped the American Civil Liberties Union into a more aggressive litigator, argued 10 cases before the U.S. Supreme Court, and supported the future Justice Ruth Bader Ginsburg in bringing a landmark sex discrimination case, died on July 8 at his home in Manhattan. He was 95.

As the legal director of the ACLU from 1962 to 1977, Mr. Wulf turned the organization from one that mostly filed friend-of-the-court briefs in others’ cases into one that directly filed suit on behalf of people who said their civil liberties had been violated.

Mr. Wulf hired the future U.S. Supreme Court justice Ruth Bader Ginsburg to co-direct the ACLU’s newly created Women’s Rights Project, which focused on sex-discrimination cases. Ms. Ginsburg won five of the six sex-discrimination cases she argued before the court during her time there.