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Kimberly Gahan

Principal Deputy General Counsel (Acting) of the Department of Defense


Kimberly Gahan is the Acting Principal Deputy General Counsel. Ms. Gahan has previously held senior legal positions in the Department of State and at the National Security Council (NSC). She served as the Principal Deputy Legal Advisor at the NSC, Special Assistant to the President, and Associate Counsel to the President from 2021-2023, where she advised senior NSC staff and the Counsel to the President on the full range of national security legal issues, including the response to Russia’s invasion of Ukraine, counter-terrorism operations, international economic initiatives, and U.S. actions to counter threats from China, Iran, and other actors.

Ms. Gahan has served in multiple senior executive positions at the Department of State, including most recently as the Assistant Legal Adviser for Nonproliferation and Arms Control, where she advised on the negotiation and application of arms control and nonproliferation agreements, implementation of U.S. sanctions and export control laws, and other efforts to counter weapons of mass destruction.

From 2017-2021, Ms. Gahan led the legal office at the State Department that advised on international economic and energy matters, where she coordinated the Department’s legal advice on economic sanctions, international trade and investment negotiations, the Committee on Foreign Investment in the United States (CFIUS), aviation agreements, and policies in international economic organizations. During this time, Ms. Gahan also led a team of lawyers in defending the United States in a case brought by Iran at the International Court of Justice challenging U.S. sanctions. From 2016-2017, Ms. Gahan led the State Department legal office supporting the Bureau of South and Central Asia and the Special Representative for Afghanistan and Pakistan.

Her prior roles at the State Department also include serving as Special Assistant to the Legal Adviser, and as Attorney Adviser for law enforcement and intelligence matters, and international claims and investment disputes. Ms. Gahan began her legal career as a law clerk to the Hon. Sonia Sotomayor on the U.S. Court of Appeals for the Second Circuit. She received her J.D. from Yale Law School and her B.A. from Yale University.