CABINET THULLIEZ
THE TEAM
HENRI THULLIEZ
Attorney at the Paris Bar, Partner
Henri THULLIEZ has been a member of the Paris Bar since 2018.
He holds a bachelor’s degree in private law from Université Paris Ouest Nanterre La Défense, an LLM in International Conflict Resolution from the School of Oriental and African Studies (University of London) and a master’s degree in public international law from Université Paris I Panthéon-Sorbonne.
He practises mainly in criminal law, international criminal law, business criminal law and corporate social responsibility. He represents several parties in proceedings under the French corporate duty of vigilance law.
Henri Thulliez has developed expertise in transnational strategic litigation in international human rights law and represents many activists, whistleblowers, journalists and political opponents.
Henri Thulliez is a founding member of the Platform to Protect Whistleblowers in Africa (PPLAAF), which he has directed since 2020. He also co-founded the association Climate Whistleblowers.
He is a member of Human Rights Watch’s Paris Committee, a board member of Sherpa, and Expert Advisor to the Rule of Law Impact Lab at Stanford University (California). He also lectures at Université d’Évry Paris-Saclay.
He was director of the Foundation for Equal Opportunity in Africa, which supports human rights and anti-corruption projects in Africa. For five years he was Human Rights Watch’s coordinator on the case of Hissène Habré, the former president of Chad tried before a special court in Senegal. He previously worked for UNRWA in Jordan.
He has been a guest lecturer at the University of Connecticut and the Salzburg Law School on International Criminal Law (2013) and has spoken at many international and academic conferences. Henri Thulliez publishes articles regularly and is experienced in high-profile cases.
Languages: French and English.
SEBASTIEN GREGOIRE
Sébastien GREGOIRE has been an associate at Cabinet Thulliez since he was admitted to the Paris Bar in 2019.
After earning bachelor’s degrees in law and in English, he went on to obtain master’s degrees in public international law and in international relations.
As part of the Human Rights Watch team in 2013 and 2015, he worked on the preparation and then the trial for international crimes of former Chadian president Hissène Habré before the Extraordinary African Chambers in Senegal.
His work covers criminal law, public international law and the corporate duty of vigilance, as well as immigration law (residence status, asylum, etc.).
Languages: French and English.
Attorney at the Paris Bar, Associate
LUCIE POURQUERY
DE BOISSERIN
Attorney at the Paris Bar, Associate
Lucie POURQUERY DE BOISSERIN has been an associate at Cabinet Thulliez since February 2025, when she was admitted to the Paris Bar, having completed her final traineeship for the Paris Bar School (EFB) at the Firm.
Lucie Pourquery de Boisserin holds a master’s degree in public international law, specialising in international criminal law, from Leiden University (Netherlands).
Passionate about international criminal law and international human rights law, she previously worked as a consultant on a defence team before the International Criminal Court and at Climate Whistleblowers, an NGO that protects climate whistleblowers.
She assists the Firm in handling its cases, particularly in criminal law and international criminal law.
Languages: French and English.