Michael J. Matheson was principal deputy legal adviser to the U.S. Department of State during 1990–2000, and acting legal adviser during substantial parts of that period. Currently he is a member of the international law faculty of the George Washington University School of Law in Washington, D.C. and a member of the UN International Law Commission. He is also on the board of editors of the American Journal of International Law and the executive council of the American Society of International Law. He was a senior fellow at the United States Institute of Peace during 2001–2002.