Old Bailey statue of Justice

Public International Law


For international lawyers, the London School of Economics has long nurtured a critical intellectual tradition. International legal research was given a firm footing from 1908, when Pearce Higgins and John Macdonell joined the department. Between the wars, several European refugees—among them Franz Neumann, Otto Kahn-Freund, Hersch Lauterpacht and Georg Schwarzenberger—joined the school as doctoral students or lecturers. In Ralf Dahrendorf’s telling, it was the infusion of this continental strain with the distinctive social science-orientation then emergent at the LSE that generated the characteristic LSE context-inflected approach to law. Neumann, for example, achieved his distinctive critical style studying under Harold Laski. Among the internationals, Schwarzenberger, who had arrived in Britain in 1934 as a Jewish refugee, undertook his doctoral research at LSE, joining the faculty in 1945. His time at LSE was marred by the opposition of Arnold McNair and Hersch Lauterpacht (both of whom taught at LSE before joining Cambridge) to his promotion to professor (ultimately he was made chair at UCL in 1962). Early courses included international law ‘with special reference to Africa’. Several postcolonial leaders—Kwame Nkrumah, Jomo Kenyatta, and BR Ambedkar among them—studied at LSE, culminating with today’s President of Barbados, Mia Amor Mottley. International law at LSE has seen countless eminent women in its classrooms—from Dame Rosalyn Higgins, judge and then President of the International Court of Justice, to Christine Chinkin FBA, Founding Director of the Centre of Women Peace & Security, with Baroness Shami Chakrabarty, long-time director of Liberty, obtaining her LLB here in 1991. 

Recent events 2022/23

25 January 2023
Moving through international courthouses: on design, emotion, and a sense of belonging
Speaker: Sofia Stolk, VU Amsterdam

26 January 2023
Global climate justice after COP27 (co-hosted with  Grantham Research Institute on Climate Change and the Environment)
Speaker: Prof Robert Falkner (LSE International Relations Department); Dr Leslie-Anne Duvic-Paoli (King’s College London Dickson Poon School of Law); Dr Stephen Humphreys (LSE Law); Dr Yusra Suedi (LSE Law) [not part of PIL@LSE series]

8 February 2023
The UN and its Infra-Law: Legalization and Lawishness
Speaker: Isobel Roele, QMUL

9 February 2023
International climate litigation: Challenges and prospects
Speaker: Panel - Margaretha Wewerinke-Singh, Paul Kingsley Clark, Monica Feria-Tinta [not part of PIL@LSE series]

15 February 2023
The planned lecture by Michael Waibel has been cancelled due to strike action.

10 March 2023
Framing preferences on international trade law
Speaker: Anne van Aaken (University of Hamburg)

14 March 2023
Evidence of the Evidence: An Empirical Study into the Elements of Customary International Law
Speaker: Massimo Lando (City University of Hong Kong)

21 March 2023
The Future of the WTO’s Dispute Settlement
Speaker: Petros Mavroidis

23 March 2023
Expert Ignorance: The Performance and Practice of Rule of Law Reform
Speaker: Deval Desai (University of Edinburgh)

23 March 2023 
'#Help: Digital humanitarianism and the remaking of international order'
Professor Fleur Johns (UNSW)
Discussants: Professor Claudia Aradau (KCL); Dr Margie Cheesman (KCL); Dr Stephen Humphreys (LSE)

29 March 2023
'The Legal Science of the International'
Speaker: Campbell McLachlan KC
Chair: Oliver Hailes 

16 May 2023
Contemporary questions on universal jurisdiction
Devika Hovell (Associate Professor and International Law, LSE); Mr Alejandro Chehtman (LSE Phd graduate and current Dean of the School of Law of the UTDT, an Argentinian University); Chris Gunness (Director of the Myanmar Accountability Project); Tomas Ojea Quintana (former Special Rapporteur on the situation of human rights in Myanmar) 

16 June 2023
'Force of Wall: The Crimes of Justice in Law and Art'
Professor Desmond Manderson (Australian National University)


Eduardo Baistrocchi is Associate Professor of Law at the London School of Economics and Political Science. He studied law at the Universidad de Buenos Aires before obtaining an LLM at Harvard Law School and later an LLM on Tax Law at LSE. He has been a Fulbright Scholar and a Chevening Scholar. He has also been a Distinguished Visiting Professor in Brazil (FGV Direito Sao Paulo), Canada (University of Toronto) and the United States (Northwestern University). His research and publications are focused on international and corporate taxation. He applies interdisciplinary approaches, such as game theory and public choice, to investigate how the international tax regime operates. He has published in leading journals and publishing houses such as the British Tax Review, Florida Tax Review, Global Tax Treaty Commentaries, the Modern Law ReviewVirginia Tax Review, the Oxford Journal of Legal Studies (OJLS) and Cambridge University Press. His OJLS piece has been considered one of the most important papers published in the last two decades on all continents. He is the principal author and editor of the first treatise offering a global analysis of tax treaty disputes in the G20 and beyond within the first century of international taxation. He is the founding Chair of the Global Tax Symposia.

Dr Chaloka Beyani is an Associate Professor of International Law at LSE Law School. He is a recognized international and United Nations expert on internally displaced persons, population transfers, mercenaries and private military companies, sexual and reproductive health, the human rights based approach to development, climate change, making treaties, and making constitutions. He has served as a legal adviser and expert to the Office of the High Commissioner for Human Rights, the Office of the High Commissioner on Refugees, the World Health Organization, the United Nations Population Fund, United Nations Development Fund for Women, the European Union, the Commonwealth Secretariat, and the African Union.

Oliver Hailes works at the interface of international arbitration and general international law, with recent focus on reconciling investment arbitration and climate change by integrating rules from international environmental law. Other publications have addressed State responsibility, lithium mining, the International Health Regulations, unjust enrichment, and histories of trade and investment law. Oliver’s doctoral research shows how the rights of States to regulate, tax and expropriate have developed through investment arbitration. He is Assistant General Editor of the ICSID Reports and is co-editing a special issue of the Journal of International Economic Law on the energy transition.

Dr Devika Hovell's research examines the capacity for international law’s enforcement. She specialises in areas such as the use of force, international criminal law, universal jurisdiction and international adjudication with a particular focus on bodies such as the UN Security Council and international courts and tribunals. She is broadly interested in whether international law can be understood as part of an international legal system, including research into international law’s sources and possibilities for cross-pollination and intersection between international and domestic legal systems. She is also interested in international law’s pluralist aspects, and the idea of comparative approaches to international law (with a particular focus on British, Russian and Chinese approaches). She is on the Editorial Board of the European Journal of International Law and is an editor of the EJIL: Talk! Blog.

Professor Stephen Humphreys's research looks at the international law dimensions of large-scale change. Having a solid grounding in climate science – a topic on which he has been active for 25 years – he has also written on international development, data governance and war, with a focus on risk allocation, distributional effects, and normative evolution. With a first degree in literature, his interests are historical, philological and transdisciplinary in nature. Stephen has worked in several international policy settings, having acted as a lead author for the Intergovernmental Panel on Climate Change, the International Bar Association, Amnesty International, and the International Council on Human Rights Policy. His work on human rights and climate change for the latter organisation, in 2007-2009, fed directly into the UN’s first studies on this matter and is widely credited with opening up what is now a vast arena of scholarly research and activism. 

Lora Izvorova is a Fellow at LSE Law School. Her research interests include public and private international law, compliance, comparative law, human rights, and legal theory. Lora also has a long-standing interest in Russian approaches to international law. Her doctoral dissertation examines the meaning of human dignity in Russia’s interpretations of the European Convention on Human Rights and the role of dignity’s contested nature as an obstacle to the Convention’s internalisation in the state. The focus of Lora’s current research is the historical and contemporary significance of the notion of state dignity in international law. Lora is a member of the ERC-funded research project Human Rights Nudge, and has previously served as Co-Convenor of the Public International Law Discussion Group at the Lauterpacht Centre for International Law at the University of Cambridge, Co-Convenor of the Cambridge International Law Conference, General Editor of the Cambridge International Law Journal, and Managing Editor of the LSE Law Review.

Dr Giulia Claudia Leonelli works in the fields of environmental and climate change law, trade and the environment, and risk regulation. Dr Leonelli’s current research projects lie at the intersection of trade and climate change law, with a particular focus on the path towards net-zero, access to critical raw materials, and new forms of environmental unilateralism and plurilateralism. Her latest publications provide a conceptually informed insight into trade-related measures that are designed to produce specific environmental effects, including anti-deforestation standards, carbon border measures, climate clubs, and Environmental Chapters in Free Trade Agreements. In the past years, she has published extensively on risk regulation and sanitary and phytosanitary measures. She regularly contributes written evidence to inquiries of the House of Commons Business and Trade Committee and the House of Lords International Agreements Committee, and in October 2023 she was invited to give oral evidence to the House of Lords International Agreements Committee regarding the UK accession to CPTPP. Dr Leonelli's research on carbon border measures and climate clubs has fed into policy discussions regarding the G7 blueprint for climate club arrangements. 

Professor Susan Marks is a Professor of International Law in the School of Law at the London School of Economics and Political Science. She graduated BA, LLB from the University of Sydney and LLM, PhD from the University of Cambridge. Before joining the LSE, she taught at the University of Cambridge and King’s College London. Her research seeks to bring insights from critical social theory to the study of international law and human rights. Her publications include The Riddle of All Constitutions, International Human Rights Lexicon (co-written with Andrew Clapham), International Law on the Left (as editor) and A False Tree of Liberty.

Dr Mona Paulsen (@loyaladvisor) is an Assistant Professor at the London School of Economics and Political Science Law School. She specialises in international trade law and economic security, in addition to research and teaching interests in international investment law, international development, and international political economy. Currently, her research evaluates the multilateral trading system’s ability to accommodate WTO members’ security concerns with economic integration within today’s geopolitical environment. In addition, she is developing a framework for assessing WTO members’ different security measures within the GATT/WTO legal order. Dr Paulsen’s forthcoming book, Before Treaties, examines the historical underpinnings of international economic law through archival research into international negotiations and states’ varied development approaches and foreign policies in the 1930s/40s. In addition to her research, Dr Paulsen serves on the editorial board for the World Trade Review.

Dr Marie Petersmann pursues research at the interface between international environmental law, human rights and critical legal theory. Her work focuses on the material, subjective, spatial, and temporal boundaries of socio-ecological harms in a changing climate, and explores new strategies for reparative legal actions and climate justice in the Anthropocene. She is currently working on a project funded by the Dutch Research Council (NWO) on Anthropocene Legalities: Reconfiguring Legal Relations within More-than-human Worlds (2022-2025). Her book, When Environmental Protection and Human Rights Collide: The Politics of Conflict Management by Regional Courts, was published with Cambridge University Press in 2022. She sits on the Editorial Board of the Review of European, Comparative & International Environmental Law (RECIEL).

Dr Margot Salomon is interested in the roles and distributional effects of international law with current projects focused on the emerging field of transformative international human rights law. Recent publications consider contradictions in the radical articulation of peasant rights; adjudicating socio-economic rights in structural context; and indigenous land rights outside of capital accumulation. Margot’s research draws inspiration from a variety of disciplines including political economy, critical development studies, and counter-hegemonic and 4th world approaches to international law. Margot has been a consultant to the UN on poverty and on the right to development, to the World Bank, and legal advisor to the President of the Greek Parliament during the debt and austerity crisis. She is a Laureate of a Belgian European Francqui Chair, winner of an ESIL book prize for the Misery of International Law (with co-authors Linarelli and Sornarajah), mother, and migrant. Margot is a member of the inaugural Editorial Board of LSE Press, a fully open access publishing house.

Professor Gerry Simpson was appointed to a Chair in Public International Law at the LSE in January, 2016. He previously taught at the University of Melbourne (2007-2015), the Australian National University (1995-1998) and LSE (2000-2007) and has held visiting positions at ANU, Melbourne, NYU and Harvard. He is the author of Great Powers and Outlaw States (Cambridge, 2004), winner of the American Society of International Law Annual Prize for Creative Scholarship in 2005 and Law, War and Crime: War Crimes Trials and the Reinvention of International Law (Polity 2007), and co-editor (with Kevin Jon Heller) of Hidden Histories (Oxford, 2014) and (with Raimond Gaita) of Who’s Afraid of International Law? (Monash, 2016). His most recent book is The Sentimental Life of International Law: Literature, Language and Longing in Global Politics (Oxford, 2021). As well as co-authoring a book entitled Rival World-Makers: The International Laws of the Cold War (Cambridge, 2024), Gerry is also writing The Atomics: My Nuclear Family at the End of the Earth, a personal meditation on nuclearism. He is a Fellow of the British Academy.

Professor Emmanuel Voyiakis has been less active in the field lately, but he maintains an interest in the theory and sources of public international law. He has published on the role of normative considerations in the formation of international custom, the contribution of UN General Assembly Resolutions to customary law-making, the place of general principles among the sources of international law, the idea of the evolutionary interpretation of treaties, and the significance for international law of debates about the objectivity of evaluative judgments.

Research Students

Irene Claeys

Parashar Das

Michelle Hughes

Carly A. Krakow

Viknes Muthiah

Bob Roth

Mikolaj Szafrański

Fletch Williams

Recent publications