Stephen Gerald Breyer (born August 15, 1938) has been a US Supreme Court Associate Justice since 1994.

Breyer was born in San Francisco, California. He married Joanna Hare in 1967, and has three children Chloe, Nell, and Michael. He received an A.B. from Stanford University, a B.A. from Magdalen College, University of Oxford, and an LL.B. from Harvard Law School. He served as a law clerk to Justice Arthur Goldberg of the Supreme Court of the United States during the 1964 Term, as a Special Assistant to the Assistant U.S. Attorney General for Antitrust, 1965-1967, as an Assistant Special Prosecutor of the Watergate Special Prosecution Force, 1973, as Special Counsel of the U.S. Senate Judiciary Committee, 1974-1975, and as Chief Counsel of the committee, 1979-1980. He was an Assistant Professor, Professor of Law, and Lecturer at Harvard Law School, 1967-1994, a Professor at the Harvard University Kennedy School of Government, 1977-1980, and a Visiting Professor at the College of Law, Sydney, Australia and at the University of Rome. From 1980-1990, he served as a Judge of the United States Court of Appeals for the First Circuit, and as its Chief Judge, 1990-1994. He also served as a member of the Judicial Conference of the United States, 1990-1994, and of the United States Sentencing Commission, 1985-1989. President Clinton nominated him as an Associate Justice of the Supreme Court, and he took his seat August 3, 1994.

Considered as a liberal judge, along with David Souter, and Ruth Bader Ginsburg, and often finds common causes with moderates Anthony Kennedy, and Sandra Day O'Connor. Breyer, along with John Paul Stevens, voiced a dissenting opinion in the Supreme Court's 2003 ruling on Eldred v. Ashcroft, where the Court ruled that the Sonny Bono Copyright Term Extension Act was not unconstitutional.

External links