Public international law

We have established a leading public international law practice and advise on international investment law, land and maritime boundary disputes, the law of the sea, sovereign and diplomatic immunity, sanctions, trade law, international environmental law, human rights, international humanitarian law, the law of international organisations and enforcement.

The experience of our team covers the spectrum of the field of public international law, ranging from state-state disputes before the International Court of Justice (ICJ) and ad hoc arbitral tribunals to advising on human rights disputes (including before U.N. committees) and international law in national courts.

We have an established investor-state arbitration practice with numerous investment treaty arbitration cases, including under the auspices of ICSID and the PCA, representing both international investors and sovereign states. We also have a leading specialist practice advising a number of Governments on drafting investment treaties and investment legislation, a rare specialism in private practice in the field of public international law.

The team includes Hussein Haeri who has fifteen years of experience of practicing public international law and international dispute resolution in London, Paris, New York and South Africa. His experience includes acting as counsel on state-state disputes such as before the ICJ. It also includes contentious and advisory work on international energy law, international environmental law, human rights, international humanitarian law and the law of the sea. Hussein has extensive experience advising Governments on treaty and legislation drafting and interpretation. He has also acted on matters of public international law in domestic courts, including in the Court of Appeal of England and Wales and the Supreme Court of the United States.

Emma Lindsay has more than fifteen years of experience of practicing public international law in New York, Geneva and The Hague. Emma represents and advises States, corporations, individuals, international organisations and non-governmental organisations. Her recent engagements span the negotiation, interpretation and application of treaties, sovereignty over territory, land and maritime boundaries, state immunity, international investment law and international human rights law. She has particular expertise in matters before the ICJ.

Aniruddha Rajput, a member of the United Nations International Law Commission, brings to the team extensive academic and professional experience in public international law.

‘The nexus between public international law and commercial issues for both Governments and multinational corporations continues to expand rapidly’, Hussein Haeri explains, ‘with the result that specialist public international law advice is increasingly needed and sought’.

The members of our team are fluent in numerous languages, including French, Spanish, Italian, Russian, Arabic and Turkish and are qualified in both common and civil law jurisdictions, with extensive experience working in international organisations and emerging markets. These key factors contribute to the strength of our practice. We are able to advise different clients, namely Governments, multinational corporations, international organisations, non-governmental organisations and individuals, in the context of sensitive disputes involving different regions of the world, including in the Middle East, Africa, Asia, CIS countries, Europe and Latin America.

Our clients have praised the team’s ‘deep technical knowledge’ and ‘impressive ability to assess and navigate complex legal and factual situations’, whilst also acknowledging our ‘responsiveness and professionalism’ as being ‘of a very high order’ and appreciating our ‘excellent customer focus’. Members of the team have also been commended for blending ‘strategic thinking with excellent client management skills’, and are known for their ‘practical and creative strategies’.

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2022 Chambers UK: leading firm for public international law

2022 Legal 500 UK, leading firm for public international law

Leading firm for public international law

Leading firm for public international law

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Track record

  • Advising a State in a potential State-to-State dispute in relation to international environmental law issues.
  • Advising a State in relation to discrimination issues arising under a human right treaty.
  • Advising a State in relation to issues pertaining to freedom of navigation and the law of the sea.
  • Advising a government in the Middle East on its investment treaty program.
  • Advising an NGO in relation to human rights issues to present a shadow letter to the UN Committee on the Rights of the Child.
  • Advising an international organisation in relation to EU-Russia sanctions.
  • Advising a German investor in an ICSID investment treaty arbitration claim in relation to discrimination measures taken by an African State.
  • Advising an Italian client in a dispute over an investment in the energy sector and ICSID investment treaty arbitration claim against a European state. Our client is seeking damages for breach of fair and equitable treatment, expropriation and other treaty standards.
  • Conducting an extensive project for a Government client advising them on international investment law issues and drafting an innovative model bilateral investment treaty.
  • Advising a Caribbean Government on a range of international investment law issues.
  • Representing a Mauritian energy company as counsel and advocates in an investment treaty arbitration against Pakistan under the UNCITRAL arbitration rules.

Hussein Haeri combines deep technical knowledge of investment treaty arbitration with clarity of strategic direction and impressive project management skills. He demonstrates excellent customer focus and sound judgement.

Thomas Le Feuvre, Head of International Agreements, Government of Jersey

Withers LLP is ‘a good firm for PIL work’; it has a particular focus on investor-state arbitration, but the practice also advises on enforcement and sovereign immunity issues, as well as human rights. Other notable areas include advising governments on the enforcement of international trusts and tax treaties; and the team has notable Middle East and energy sector expertise. Hussein Haeri is ‘very strong’; he led the representation of a UK investor in an International Centre for Settlement of Investment Disputes arbitration against the Czech Republic.

Legal 500, 2017

Hussein Haeri impresses market commentators with his ‘combination of strong litigation skills with expert knowledge in public international law.

Who's Who Legal, 2017

Withers LLP is very strong in this field with a real diversity of work across all types of public international clients. The practice is particularly well-known for its investor-state arbitration practice as well as state-state disputes; notable geographical strengths include the Middle East and Africa and the team regularly works on infrastructure and energy-related matters. It is also noted for human rights and trade law issues. Highlights included representing A11Y, which specialises in assistive technology solutions for blind people, in an ICSID-administered investor-state arbitration against the Czech Republic under the UK-Czech Republic bilateral investment treaty. Public international law head Hussein Haeri combines huge intellectual powers with great client handling and gives straight-to-the-point advice.

Legal 500, 2019

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