Defensor Santiago went on a fellowship to the United States, and earned the Master of Laws and Doctor of Juridical Science degrees at the University of Michigan, Ann Arbor. She finished both degrees in a period of only one and a half years. Following school, she took a position as special assistant to the Secretary of Justice. She also taught political science at the Trinity University of Asia. She was law professor at the University of the Philippines Diliman, teaching evening classes for some ten years.