Public International Law
Key contact
The Public International Law Group has more than 30 years’ experience advising sovereign States and their emanations, international organisations and commercial entities on disputes before the domestic courts and international courts and tribunals, as well as advising on non-contentious matters.
Our team supports clients on a broad range of public international law issues, including privileges and immunities, enforcement, obtaining evidence for use in overseas proceedings, expropriation, the law of the sea, treaty law, State responsibility, international institutional law and the application of EU and UK sanctions rules.
We also regularly advise on Investor-State arbitrations, with CMS specialists from across our network of global offices pooling their skills and expertise within the CMS Investment Arbitration Task Force.
Our experience includes advising:
- Pakistan in successfully dismissing the Nuclear Disarmament Case brought by the Republic of the Marshall Islands before the International Court of Justice.
- The Caribbean Regional Fisheries Mechanism (17 Member States) in Case 21 before the International Tribunal for the Law of the Sea in Hamburg.
- The Government of a Caribbean country in a fisheries-related dispute with the European Commission.
- Erste Group Bank AG in a treaty-based investment arbitration against the Republic of Croatia before the World Bank’s International Centre for Settlement of Investment Disputes (ARB/17/49).
- The United States of America in relation to whether it is bound to consult with its local civilian employees about redundancies before closing a military base, and how domestic statutes should be interpreted to give effect to customary international law, United States of America v Nolan [2015] UKSC 63, Supreme Court.
- The US Securities and Exchange Commission in its successful application for the continuance of a freezing injunction unanimously upheld by the Court of Appeal, in what is believed to be the first decision of its kind in granting the order to a foreign claimant without the requirement for a cross undertaking in damages,
- The US Secretary of State for Health in obtaining one of the first orders of its kind for disclosure by a third party under CPR5.4C(2) for the provision of various medical reports from the UK MMR litigation for use in the US MMR autism group litigation, Sayers & Ors v Smithkline Beecham Plc & Ors [2007] EWHC 1346 (QB).
- The United States of America in its successful assertion of state immunity in the House of Lords, Holland v Lampen-Wolfe [2000] 1 WLR1573.
- Kuwait Airways and the State of Kuwait in connection with claims and associated appeals arising out of the invasion of Kuwait in 1990. The resulting judgments re-wrote the law books on State Immunity and Act of State doctrine in the House of Lords, (1995) 1 WLR 1147 (HL); (2001) 1 WLR 429 (HL), (2002) (No. 6) 2 AC 883 (HL); and (2010) 2 S.C.R. 571.
- Fugro, the world’s leading Geo-data specialist headquartered in The Netherlands, in connection with public international law, in particular the Law of the Sea, aspects of Fugro’s geo-data services (especially surveys) to its customers worldwide.
- The Government of St Vincent and the Grenadines on its ongoing dispute with the European Commission following the black-listing of SVG due to alleged IUU fishing activities by SVG-flagged vessels.
- Patel Engineering Limited (“PEL”), the largest private infrastructure and construction services company in India, in Patel Engineering Limited (India) v. The Republic of Mozambique (PCA Case No. 2020-21).
Further reading
Legal experts for Public International Law



Local market knowledge. Global outlook
We provide future-facing legal advice to help your organisation thrive. Combining local market knowledge and a global perspective, and with lawyers in locations worldwide, your organisation benefits from the expertise it needs, even across borders.
About CMS