Jeffrey Sizemore, Executive Director & Visiting Professor
Jeff Sizemore is a global leader on atrocity prevention training for practitioners. He is the 2026 Mary Wing-Ming Lee Senior Human Rights Research Fellow for the Asia Pacific Centre for the Responsibility to Protect at the University of Queensland and a visiting professor at George Mason University and Keene State College. He advocates publicly on the value of atrocity prevention as well as working with students entering the human rights and atrocity prevention enterprise. Previously, he served as the Deputy Director in the Office of Security and Human Rights and as the Senior Advisor on Atrocity Prevention for the Bureau of Democracy, Human Rights, and Labor at the United States Department of State. He led and coordinated the bureau’s atrocity prevention efforts, managing atrocity prevention training for the Department, coordinating with interagency colleagues as part of the Atrocity Prevention Task Force, and representing the United States in multilateral atrocity prevention activities.
Prior to joining the State Department, Jeff served for over 20 years in the United States Navy as a Surface Warfare Officer, retiring as a commander in 2020. Jeff received a bachelor’s degree in American Studies from the George Washington University in 2001 and a master’s degree in National Security and Strategic Studies from the United States Naval War College in 2012. Additionally, he is the Deputy Director of Former, Feds and Friends and as a consultant with Collaborative Structural Change.
D. Wes Rist, Esq., Deputy Executive Director
D. Wes Rist is an atrocity prevention professional with nearly 20 years of experience in international human rights law, transitional justice, and international criminal justice. He is currently the Deputy Executive Director of the Genocide Prevention Program and a Ph.D. student in atrocity prevention at the Jimmy and Rosalynn Carter School for Peace and Conflict Resolution at George Mason University. He previously served as Atrocity Prevention Policy Advisor in the Bureau of Conflict & Stabilization Operations at the U.S. Department of State and as the Deputy Executive Director at the American Society of International Law. He has advised civil society organizations, governments, and international organizations around the world on atrocity prevention policy and international human rights law. Wes holds a JD and an LL.M. (with distinction) in international human rights law. He is on LinkedIn.
Douglas Irvin-Erickson, Faculty Director
Douglas Irvin-Erickson is a political theorist and diplomatic historian working in international criminal law, global justice, and genocide prevention. A full list of his publications can be found on his personal website. At the Carter School, he is the faculty director of the Mass Atrocities Prevention Program. Irvin-Erickson is a Senior Fellow with the Alliance for Peacebuilding, a Board Member of the Institute for the Study of Genocide, and a member of the editorial board of Genocide Studies and Prevention: An International Journal. He holds a Ph.D. in Global Affairs and an M.A. in English Literature from Rutgers University, in Newark, NJ, USA.
Meghan Garrity, Core Faculty
Her research is situated at the nexus of international peace and security, political violence, and forced migration. She is focused on understanding conflict processes by examining the causes of, and constraints on, government policies of group-based ethnic violence and exclusion. Her book, Mass Expulsion: The Politics of Forced Population Removal (Oxford University Press – Bridging the Gap Series, 2026), explains why and how governments expel ethnic groups en masse. Garrity’s work is published in the Journal of Peace Research, Security Studies, Political Science Quarterly, International Political Science Review, TheBritish Journal of Sociology, the Journal of Ethnic and Migration Studies, International Affairs, The Conversation, and The Washington Post. She also has over ten years of experience as a humanitarian and development practitioner throughout sub-Saharan Africa and the Middle East.
Garrity was previously a Postdoctoral Fellow at the Belfer Center for Science and International Affairs at the Harvard Kennedy School, and a Peace Fellow with the U.S. Institute of Peace. She received her PhD in political science from the University of Pennsylvania.
Areas of Research: International security, Ethnic violence, Mass atrocities, Forced migration, Refugees, Human Rights.
Sixte Vigny Nimuraba, Research Professor
Sixte Vigny Nimuraba, PhD, is the president of the Burundi Independent National Commission on Human Rights (CNIDH) since April 2019. He is also an International Advisory Council Member at the Institute of One World Leadership and a lecturer at the national university of Burundi. In the past, he was a Visiting Scholar and the Director of Violence Prevention Initiative in the School for Conflict Analysis and Resolution (S-CAR) at George Mason University (GMU) and later a practitioner-in- residence at Binghamton State university of New York. He is a PhD from S-CAR / GMU. He was the Dean’s Assistant, FIPSE administrator, teaching assistant, online teacher of several courses such as Early Warning Systems and Atrocity Prevention and preventing identity based violence at Auschwitz Institute for Peace and reconciliation. He has extensive experience working with Burundian civil society and non-governmental organizations to promote human rights, peace, conflict prevention and escalation, social cohesion in general and integration of returnees in local communities. Before joining Ligue Iteka, Vigny held different positions in local and international organizations such as VISPE, Care International, and CNLS, which inspired his passion to dedicate his life to the quest for peaceful coexistence and social cohesion in Burundi and the African Great Lakes region. Vigny holds a Bachelor’s degree in Economics from University of Ngozi (Burundi) and a Master’s degree from George Mason university (USA).
Madeline Vellturo, PhD Researcher
Madeline Vellturo is a research analyst and policy practitioner with more than 12 years of experience working on stabilization, peacebuilding, and violence prevention in sub-Saharan Africa. Areas of expertise include countering violent extremism, atrocity prevention, civilian protection, UN peacekeeping, identity-based conflict, rural livelihoods, and natural resource management. She is currently an Advisor with Strategic Stabilization Advisors and a PhD candidate at George Mason University’s Carter School for Peace and Conflict Studies. She is also co-founder, Director, and host of Former Feds & Friends, a new media initiative using popular film and television to make lessons in violence prevention from around the world accessible to wider audience. Madeline previously served as a Research Analyst with the Stimson Center’s Protecting Civilians in Conflict Program, a Senior Policy Analyst at the U.S. Commission on International Religious Freedom, and a Stabilization Advisor with the State Department’s Conflict and Stabilization Operations Bureau. She received a Bachelors degree from Bryn Mawr College and a Masters degree from Columbia University’s School of International and Public Affairs. She has lived and worked abroad in Guinea, Ghana, Cote d’Ivoire, Kenya, and Uganda, and conducted field research in Mali, Central African Republic, Nigeria, South Sudan, and Democratic Republic of Congo. https://express.adobe.com/page/hDXrZUSxQv6Sw/
Rafiki Ubaldo, Research Director
Rafiki Ubaldo is a Doctoral Candidate at The Jimmy and Rosalynn Carter School for Peace and Conflict Analysis, and a George Mason University Presidential Scholar. Before joining The Carter School, he worked in professional services in the Department of Special Education at Stockholm University and at Lund University School of Economics and Management in Sweden. He holds a Bachelor of Science in Political Science from Stockholm University and a Master of Arts in Holocaust and Genocide Studies from Uppsala University in Sweden. He is a photojournalist, published scholar, and writer. A veteran journalist, he worked in East Africa and Europe. He is a co-editor of a book on oral histories of the Genocide against the Tutsi in Rwanda, a book on music and peacebuilding, and several book chapters. His short story debut, “The Bullet,” was published in Two Third North, and translated and published in Polish, Portuguese, Finnish and Swedish. His photography sits at the intersection of documentary and creative expression, exploring the conditions that shape our lives. A portfolio is available here: www.templesofmemory.org. The album Only Love by Jean Paul Samputu features songs such as Timbuktu Mon Amour and other poems written by Rafiki. He has served as an Executive Board member of The International Association of Genocide Scholars (IAGS) and the Editorial Board of Genocide Studies and Prevention: An International Journal. In Rwanda, he advocated for the study of genocide and prevention, and is honored to have served on the team that created the Masters Programme in Genocide Studies and Prevention at The Center for Conflict Management, University of Rwanda. He is past Vice-President and current board member of Capacitar Rwanda. In 2025, Rafiki Ubaldo was appointed Community Director and Reviews Editor for Peace Chronicle, the Magazine of Peace and Justice Studies Association (PJSA).
Colby Siegismund, Communications Director
Colby is pursuing a Bachelor of Science in Conflict Analysis and Resolution at The Jimmy and Rosalynn Carter School for Peace and Conflict Analysis, with a concentration in Global Engagement and a minor in History. At the Carter School, he supports the Mass Atrocities Prevention Program as its Director of Communication and Web Developer, shaping the program’s digital presence and public communications. Siegismund is an emerging leader in the Armed Forces Communications and Electronics Association, Washington, D.C., chapter.