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Margaret E. (Peggy) McGuinness

Professor of Law
Director, LL.M. in Transnational Legal Practice
Co-Director, St. John’s Center for International and Comparative Law
B.A., American University
J.D., Stanford Law School

Peggy McGuinness joined the St. John’s faculty in 2010. Professor McGuinness researches and teaches in the areas of international law and international human rights law, and she has published widely on the subjects of international human rights law, international security and the resolution of armed conflict, and the role and influence of international law in the United States.  Her most recent book chapter, “Treaties and Federalism,” addresses balancing federalism with enforcement of U.S. treaty obligations and will appear in Treaties as Law of the Land? Change and Uncertainty in the Domestic Effects of International Agreements, (Gregory H. Fox, Paul R. Dubinsky & Brad R. Roth, eds. Cambridge Univ. Press) in Spring 2017. Her current course offerings include International Law, International Human Rights, and the Transnational Legal Practice for LL.Ms.

Professor McGuinness serves on the Council on International Affairs of the New York City Bar and the Executive Committee of the International Section of the New York State Bar Association, where she is also co-chair of the Public International Law Committee. She is an active member of the American Society of the International Law, where she served on the Executive Council, and the International Law Association, where she serves on the Committee on Recognition/Non-Recognition, and the International Section of the American Bar Association. She co-founded Opinio Juris, the leading international law blog.

Professor McGuinness graduated with distinction from Stanford Law School, where she was an articles editor for the Stanford Law Review and a graduate fellow at the Stanford Center on Conflict and Negotiation. Afterwards, she clerked for Judge Colleen McMahon in the Southern District of New York and worked as a litigator for Paul, Weiss, Rifkind, Wharton & Garrison LLP. Her career in the law follows an early career as a Foreign Service Officer with the State Department, which included service in Germany, Pakistan and Canada, and as a Special Assistant to Secretary of State Warren Christopher.

Professor McGuinness previously taught at the University of Missouri School of Law. She has also been a visiting professor at the University of Georgia and Temple University, and a visiting scholar at the Johns Hopkins School of Advanced International Studies.