Ramsey is the Warren Distinguished Professor of Law at the University of San Diego School of Law, where he teaches and writes in the areas of Constitutional Law, Foreign Relations Law and International Law. Ramsey clerked for Judge J. Clifford Wallace of the U.S. Court of Appeals for the Ninth Circuit and for Justice Antonin Scalia of the U.S. Supreme Court. He practiced international business law with the firm of Latham & Watkins before joining the USD School of Law faculty in 1995.