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Working Group on Arbitrary Detention

The Working Group is composed of five independent experts appointed by the Human Rights Council. All members serve in their personal capacities. A mandate-holder’s tenure is limited to a maximum of six years.

The Working Group holds three sessions per year, usually in April, August and November, each lasting between five to ten working days. At the end of its April session every year, the members of the Working Group elect their Bureau, comprised of the Chair-Rapporteur, Vice-Chair on Communications and Vice-Chair on Follow-up.

Since 2017, the Working Group also appoints a focal point on reprisals from among its members. The working languages of the Working Group are English, French and Spanish.

Current members

Dr. Matthew Gillett (New Zealand), appointed in 2022 - (Chair-Rapporteur)

Dr. Matthew Gillett earned his PhD in international law from the University of Leiden. His LLM is from the University of Michigan and his BA and LLB are from the University of Otago. He has over 20 publications on international law and human rights, and he won the inaugural Benjamin Ferencz prize for his article on prosecuting the crime of aggression before the International Criminal Court. He is a Senior Lecturer (Associate Professor) at the University of Essex, where he co-leads the Digital Verification Unit. He has researched and taught on human rights, criminal procedure, and terrorism at various universities and institutions around the world. Matthew Gillett is an experienced international lawyer and human rights specialist. He has investigated and prosecuted war crimes, crimes against humanity and genocide for over 15 years. He worked as a Trial Lawyer and Appeals Counsel at the International Criminal Court and the United Nations International Criminal Tribunal for the former Yugoslavia and has conducted investigations in various conflict zones. He also worked as a Human Rights Officer for the United Nations Assistance Mission in Afghanistan. He participated in negotiating the crime of aggression at the International Criminal Court review conference in Kampala in 2010. He was appointed to the Working Group in 2022.

Dr. Ganna Yudkivska (Ukraine), appointed in 2022 - (Vice-Chair on Communications)

Ganna Yudkivska

Dr. Ganna Yudkivska is a Ukrainian lawyer and former Judge of the European Court of Human Rights.

She is a director of the Centre de la Protection International (Strasbourg, France), and Board Member of the European Society of International Law.

Dr. Yudkivska graduated from the Law Faculties of the Taras Shevchenko Kyiv National University (Ukraine) and Université Strasbourg III (France).

She has her PhD diploma from the Academy of Advocacy of Ukraine
In 2010 GannaYudkivska was elected a Judge of the European Court of Human Rights; in 2015–2016 she was Vice-President of Section V of the Court, in 2017 - 2019 she was President of Section IV of the Court.  She served on the bench for twelve years, until the end of June 2022.

Prior to that Dr. Yudkivska has held a variety of positions in the field of human rights and rule of law - between 2001 and 2005 she worked as a lawyer and expert for different international and national human rights organizations; in 2005-2009 she was a lawyer at the Registry of the European Court of Human Rights; and in 2009-2010 she was an advisor to the Commissioner for Human Rights of the Council of Europe.

In 1995-2001, she led in Ukraine and Moldova the legacy project on genocide studies (now – Shoah Institute of the University of South California), and also served as human rights and national minorities expert for the Congress of National Minorities of Ukraine.

Dr. Yudkivska has taught public international law and human rights law at numerous universities of USA, France, Germany, UK, the Netherlands, Israel and Ukraine. She authored a number of scientific articles on human rights, international law and criminal procedure; she is also a member of the advisory boards of several legal magazines. She was appointed to the Working Group in 2022.

Ms. Priya Gopalan (Malaysia), appointed in 2021 - (Vice-Chair on Follow-Up)

Ms. Priya Gopalan is a Malaysian lawyer specialising in international criminal law, human rights law, and gender. Her expertise is in international criminal prosecutions, strategic litigation, advocacy and human rights investigations in conflict and post-conflict settings, as well as other transitional justice processes. Her work has included operationalising reparations for survivors of sexual violence, developing technical guidance and policy on issues such as access to justice and, best practices for working with survivors of grave crimes. Her experiences cover Kosovo, Bosnia, Croatia, Ukraine, Georgia, Armenia, Moldova, Sri Lanka, Syria, and The Gambia. She provides expert advice to international and national bodies, UN agencies, states, and civil society organisations.

Ms. Gopalan has held a variety of positions in the field of transitional justice and accountability. She was a prosecutor and appeals counsel at the UN International Criminal Tribunal for the former Yugoslavia, where she played a leading role in cases that developed progressive legal precedents on conflict-related sexual violence. Ms. Gopalan served as the first Legal Advisor for sexual and gender-based crimes at the International, Impartial and Independent Mechanism to Assist in the Investigation and Prosecution of Persons Responsible for the Most Serious Crimes under International Law Committed in the Syrian Arab Republic (the IIIM Syria). She has held several roles in the Office of the High Commissioner for Human Rights (OHCHR), including Gender Advisor for the OHCHR Investigation on Sri Lanka. Ms. Gopalan also served as Senior Advisor to the Truth, Reconciliation and Reparations Commission of The Gambia.

Ms. Gopalan qualified as a solicitor in England and Wales in 2002. She holds a LL.M in Public International Law (Distinction) from the London School of Economics and Political Science and a B.A. Jurisprudence (Hons) from the University of Oxford, where she was a UK Foreign and Commonwealth Office Chevening Scholar from Malaysia. She was appointed to the Working Group in 2021.

Dr. Miriam Estrada-Castillo (Ecuador), appointed in 2020 

Dr. Miriam Estrada-Castillo is a Professor of International Law, International Criminal Law and Human Rights and the Director of the UNESCO Chair at Casa Grande University, of Guayaquil, Ecuador. She is also a Visiting Professor at Bards College (NY/Palestine). 

Dr. Estrada worked for the United Nations Security Council Counter-Terrorism Committee Executive Directorate (CTED) and as an International Prosecutor in Timor-Leste being part of the first 100 Brahimi Civilian Experts deployed in a Peacekeeping Mission by the UN. She is a former Vice chairperson of the Committee for the Elimination of all Forms of Discrimination against Women (CEDAW) and member of the group which drafted the CEDAW Optional Protocol.

Dr Estrada was the Latin America Regional Adviser on Gender, Human Rights and Culture of Peace for UNESCO. 

She has been Visiting Professor and International Leading Expert on Human Rights at the Raoul Wallenberg Institute of Human Rights and Humanitarian Law (RWI), Professor in Residence at the UN University for Peace and at the Australian National University, former Minister of Social Affairs and a former President of the National Court for Minors in Ecuador. She is the author of the Children’s and Family Law of her country and is known as the founder of the Human Rights Education on Ecuador. She has written profusely about Human Rights, Gender and Civil and Political Rights. She was appointed to the Working Group in 2020.  

Dr. Mumba Malila (Zambia), appointed in 2020

Dr. Mumba Malila holds a Doctor of Laws degree (LLD) in Human Rights from the University of Pretoria and LLM degrees from Cambridge and Cumbria universities. He is presently  the Chief Justice of Zambia. He previously taught law at the University of Zambia. He was once Chairperson of the Zambian Human Rights Commission during which time he among other things undertook country-wide visitation of prisons and other places of detention in Zambia and engaged authorities to improve conditions of detention. He later served twice as Attorney General of Zambia. He also served as a Member and subsequently as Vice Chairperson of the African Commission on Human and Peoples’ Rights. He was Special Rapporteur on Prisons and Conditions of Detention in Africa for four years. He was appointed to the Working Group in 2020.

Former members

Ms. Elina Steinerte (Latvia), 2016-2022
Ms. Leigh Toomey (Australia), 2015-2022
Mr. Seong-Phil Hong (Republic of Korea),2014-2021
Mr. Sètondji Roland Adjovi (Benin), 2014-2020
Mr. José Guevara Bermúdez (Mexico), 2014-2020
Mr. Vladimir Tochilovsky (Ukraine), 2010-2016
Mr. Mads Andenas (Norway), 2009-2015
Ms. Shaheen Sardar Ali (Pakistan), 2008-2014
Mr. El Hadji Malick Sow (Senegal), 2008-2014
Mr. Aslan Abashidze (Georgia), 2008-2010
Ms. Manuela Carmena Castrillo (Spain), 2004-2009
Mr. Seyyed Mohammad Hashemi (Islamic Republic of Iran), 2002-2008
Ms. Soledad Villagra de Biedermann (Paraguay), 2002-2008
Ms. Leïla Zerrougui (Algeria), 2001-2008
Mr. Tamás Bán (Hungary), 2001-2008
Mr. Roberto Garretón (Chile), 1992-2002 and 2008-2014
Mr. Louis Joinet (France), 1992-2003
Mr. Laity Kama (Senegal), 1992-2001
Mr. Kapil Sibal (India), 1992-2001
Mr. Petr Uhl (Czech Republic), 1992-2001