Tomas Hamilton is a UK lawyer with a specialized focus on arms regulation and the role of criminal law in providing accountability for unlawful arms transfers. He has worked for over a decade in the United Nations and international criminal tribunals, contributing to cases of genocide, war crimes, and crimes against humanity. Hamilton has been actively involved in academia, serving as an Assistant Professor of International Criminal Law at the University of Amsterdam and engages widely with issues of corporate accountability and the arms trade.

Hamilton's expertise in the intersection of arms regulation and criminal law led to his forthcoming book, The Arms Trade and International Criminal Law (Oxford University Press, 2024). This work delves into the potential for the International Criminal Court (ICC) and other forums to hold individuals accountable for providing the means to commit atrocities and explores why this has not yet taken place.

Hamilton has primarily worked with the International Criminal Court (ICC), the United Nations Assistance to the Khmer Rouge Trials (ECCC/UNAKRT), and the United Nations Office of the High Commissioner for Human Rights (OHCHR-FFM) on Venezuela. He has also contributed to projects for organizations such as Amnesty International, Global Witness, and the International Committee of the Red Cross (ICRC). Early in his career, he worked at Bark & Co Solicitors in London, focusing on business crime, and gained experience in media and communications through roles at the BBC and TED Talks.

Hamilton is called to the Bar of England and Wales (2011) and is based at Guernica 37 Chambers in London.