Duncan B. Hollis

Laura H. Carnell Professor of Law
Co-Faculty Director, Institute for Law, Innovation & Technology
Director, LL.M. and J.D./LL.M. in Transnational Law

Duncan B. Hollis is Laura H. Carnell Professor of Law at Temple Law School and co-faculty director of Temple’s Institute for Law, Innovation & Technology (iLIT). His scholarship engages with issues of international law, interpretation, and cybersecurity, with a particular emphasis on treaties, norms, and other forms of international regulation.

Hollis is currently a non-resident Scholar at the Carnegie Endowment for International Peace and an appointed member of the U.S. Department of State’s Advisory Committee on International Law. Together with Oxford University Professor Dapo Akande, he is co-convenor of the Oxford Process on International Law Protections in Cyberspace and its accompanying Compendium. Professor Hollis is also an elected member of the American Law Institute, where he serves as an Adviser on its project to draft a Fourth Restatement on the Foreign Relations Law of the United States. From 2016-2020, he served as a member of the OAS’s Inter-American Juridical Committee, including as Rapporteur for projects on binding and non-binding agreements and  improving the transparency of State views on international law’s application to cyberspace. Hollis has spent time as a Senior Fellow at Melbourne Law School, a Visiting Professor at LUISS Università Guido Carli, and a Visiting Scholar at the University of Pennsylvania’s Perry World House.

Professor Hollis’s books include The Oxford Guide to Treaties (OUP, 2nd ed., 2020), the first edition of which received the 2013 ASIL Certificate of Merit for high technical craftsmanship and utility to practicing lawyers; International Law (Aspen, 8th ed., 2023) (with Allen Weiner and Chimène Keitner); and Defending Democracies: Combatting Foreign Election Interference in a Digital Age (OUP, 2021) (with Jens Ohlin). His articles have appeared in various journals and books, including the American Journal of International Law, European Journal of International Law, Texas Law Review, Southern California Law Review, Harvard Journal of International Law, Vanderbilt Journal of Transnational Law, and Virginia Journal of International Law.

Professor Hollis received an A.B., summa cum laude, from Bowdoin College. In 1996, he completed a joint-degree program, receiving a Masters in International Law and Diplomacy from the Fletcher School at Tufts University and a Juris Doctor, summa cum laude, from Boston College Law School.

Following graduation, Professor Hollis worked for the International Department of Steptoe & Johnson LLP. In 1998, Professor Hollis joined the Office of the Legal Adviser at the U.S. Department of State, where he worked until joining the Temple faculty in 2004. During his tenure at the State Department, Professor Hollis served for several years as the attorney-adviser for treaty affairs, working on legal and constitutional issues associated with the negotiation, conclusion, and implementation of U.S. treaties. Professor Hollis’s practice has included international litigation before the International Court of Justice. In particular, he served as Counsel to the United States in the provisional measures phase of the Case Concerning Avena and Other Mexican Nationals (Mexico v. United States) and contributed to the U.S. presentation in the Oil Platforms Case (Iran v. United States), with the latter role earning him the State Department’s Superior Honor Award. Today, he continues to participate in investor-state aribrations in various compacities while also advising various international organizations and consulting regularly, including advising the Microsoft Corporation on its Digital Peace agenda.


M.A.L.D., Fletcher School of Law and Diplomacy (Tufts University)
J.D. (summa cum laude), Boston College Law School
A.B. (summa cum laude), Bowdoin College

Research & Teaching Areas

Areas of Expertise

Selected Publications

Publications and Media Appearances SSRN


  • Member, American Law Institute

Selected Conferences

    • Lecturer, Treaties and Non-Legally Binding Instruments – Status and Treatment in International and Domestic Law, United Kingdom Foreign, Commonwealth & Development Office, Seminar Series, Virtual Discussion, May 2023
    • Panelist, Enforcement Challenges in Cyberspace, Symposium on Reassessing Enforcement: Strengthening Compliance with International Law, Harvard Law School, Boston, MA, March 2023
    • Presentation, Threatening Force in Cyberspace, Faculty Colloquium, Ohio State Moritz College of Law, Columbus, OH, March 2023
    • Panelist, Suspension/Termination of Treaties in Armed Conflicts and Other Emergency Situations, 32nd Informal Meeting of Legal Advisers, United Nations General Assembly, New York, October 2022
    • Co-Convenor and Presenter, The Oxford Process on International Law Protections in Cyberspace,  Oxford University, Hybrid Workshop, Oxford, United Kingdom, October 2022
    • Co-Convenor, Lead Expert, The Prohibition on the Use of Force, Tallinn Workshop on International Law and Cyber Operations, Republic of Estonia Ministries of Defense and Foreign Affairs/NATO CCD COE, Workshop, Tallinn, Estonia, September 2022
    • Paper Presenter, Do International Agreements have a Consent Problem? Consenting to International Law, Collège de France, Paris, June 2022
    • Treaty Expert and Presenter, UNCITRAL Working Group III (Investor-State Dispute Settlement Reform), Informal Meeting of Delegates, Hybrid Session, Vienna (June 2022).
    • Co-Convenor and Moderator, The Oxford Process on International Law Protections in Cyberspace, Countermeasures, Oxford University Blavatnik School of Government, Hybrid Workshop, Oxford, United Kingdom, May 2022
    • Presenter, From Regulation to Effectiveness: Information Operations and International Law, Vanderbilt Law School, Virtual Conference, February 2022
    • Presenter, The Many Sounds of State Silence in Cyberspace, State Silence, University College London, Hybrid Workshop, December 2021
    • Presenter, Peaceful Settlement and International Law, Hebrew University, Federmann Cyber Security Research Center, Virtual Workshop, December 2021
    • Presenter, Binding and Non-Binding Agreements in International Relations, Peruvian University of Applied Science, Second Seminar on International Law, October 2021
    • Commentator, Non-Binding International Agreements; A Comparative Assessment, University of Chicago School of Law, Virtual Workshop, September 2021
    • Presenter, The OAS Experience, Non-Legally Binding Agreements in International Law, Council of Europe, The Committee of Legal Advisers of Public International Law (CAHDI), Virtual Expert Workshop, March 2021
    • Presenter, Binding and Non-Binding Agreements, Oxford University Faculty of Law, Public International Law Discussion Group, Virtual Meeting, January 2021
    • Co-Organizer & Presenter, An Overview of Treaty Interpretation, Principles of Treaty Interpretation—Does Vienna Wait for You?, American Bar Association, International Law Section, Virtual Workshop, December 2020
    • Presenter, Presentation of the Guidelines of the Inter-American Juridical Committee for Binding and Non-binding Agreements, Organization of American States, Secretariat for Legal Affairs, Virtual Session, November 2020
    • Panelist, Cyber Operations during an Armed Conflict, Bruges Colloquium, International Committee of the Red Cross and College of Europe, Virtual Meeting, October 2020
    • Presenter, Defending Democracies via Cybernorms, University of Michigan Law School, Faculty Colloquium, Virtual Meeting, September 2020