Matt is an Associate Professor in Law at Sussex Law School, and he is the Co-Founder and Co-Director of Sussex Terrorism and Extremism Research Network (STERN). 

Matt’s research expertise is centred around the intersection between domestic law, international law and international cooperation. In international law, Matt specialises in State extraterritorial jurisdiction (State power to regulate persons, companies and activities beyond national borders), immunities from jurisdiction and complex cross-border prosecutions and civil litigation. Additionally, Matt specialises in legal regimes (domestic criminal law and international law) countering terrorism and forms of transnational (cross-border) crime.  

Matt has worked as an independent expert advisor on counter-terrorism at the United Nations, a role which included the delivery of major research projects for the United Nations to inform global policy, and making recommendations to Member States, based on best practices, on (1) countering the causes of terrorism and its links with organised crime and (2) the implementation of relevant international legal frameworks (multilateral treaties and United Nations Security Council Resolutions) in domestic law for the criminalisation, investigation and prosecution of transnational terrorism and consistent with international human rights law. Under the auspices of the United Nations, Matt has contributed to high-level international conferences and expert group meetings on the subject of terrorism and organised crime. This experience has given Matt extensive knowledge and understanding of law and practice in numerous countries globally, spanning Africa, the Americas, Asia and Europe. 

Matt has a strong track-record of producing world-leading research to inform policy, practice and scholarship in his field of expertise. With his depth and breadth of knowledge, Matt's research is adept at challenging long-standing assumptions and conventional wisdom, leading to new or different ways of thinking, to the development of new concepts and conceptual models, and to proposals for law reform. 

Matt is a peer reviewer for numerous publishers, including Bloomsbury, Edward Elgar, Cambridge University Press, Oxford University Press and Routledge.

Matt’s professional activities include:

2025–Present:  Advisor to UK Parliamentary briefings on the Yazidi genocide and legal responses for criminal accountability.

2023–Present: Expert for the ‘Criminal Law Reform Now Network’ working in collaboration with the Law Commission of England and Wales. Read our Report which proposes law reform relating to criminal jurisdiction, mutual legal assistance and extradition: Davies, G., Arnell, P., Davidson, R., Eskauriatza, J., Matthew Garrod, Keith, B., Marks, E., Niblock, R., Ó Floinn, M., Shurson, J., & Vamos., N. (2025). International Cooperation and Extradition Scoping Review. Criminal Law Reform Now Network. Professor Penney Lewis, Commissioner for Criminal Law, described our Report as follows: 

"This is a serious, thorough and most importantly useful piece of work which will help to set the terms of the debate for law reform in this area. The review has opened up discussion within and outside government and provides a strong rationale for pursuing law reform. This review fulfils the promise of the Memorandum of Understanding agreed between the Law Commission and CLRNN in 2023. We have worked together productively without compromising the independence of either organisation."

2023–Present: Expert Advisor on jurisdiciton and extradition for ECPAT International (End Child Prostitution and Trafficking): https://ecpat.org/.

2022–Present: Expert Member for the UK Government Research and Innovation Talent Peer Review College, with the responsibility for providing independent and informed peer review of major research funding proposals across a range of disciplines.

2022–Present: Expert Advisor for the UK Government Commonwealth Scholarship Commission, Foreign Commonwealth and Development Office, with responsibility for the selection of candidates for scholarships and fellowships across a range of disciplines.

2017–Present: Independent Expert Advisor on Counter-Terrorism and International Law at the United Nations Office on Drugs and Crime. This role includes providing in-depth reviews of national laws and procedures and making recommendations for national law reform based on findings of fact and informed by international best practices.

2017–Present: Counter-Terrorism Expert for the 'Education for Justice (E4J)' project, organised under the auspices of the United Nations Office on Drugs and Crime.

2017–2019: Co-Lead Investigator on the first Education for Justice project working in collaboration with the Terrorism Prevention and Organised Crime Branches of UN Office on Drugs and Crime, titled 'Strengthening Research and Evaluation Capacity on Linkages Between Organized Crime and Terrorism Within Tertiary Institutions Globally'. One of the outputs from this project was the co-authored University-level module series for use as a teaching tool at university institutions globally.

2017–Present: Research Fellow, European Foundation for South Asian Studies.

2015: Research Fellow, British Institute of International and Comparative Law, Russel Square, London.

2009: Independent Expert on Diplomaic and Consular Assistance and Protection provided to British and EU nationals overseas as part of a wider EU project titled 'Citizens Consular Assistance Regulation in Europe'. The study was funded by the European Commission and the published report is available here: http://www.ittig.cnr.it/Ricerca/ConsularAndDiplomaticProtection.pdf

Research Expertise:

Matt’s area of research expertise is centred around the intersection between criminal law, international law, terrorism and counter terrorism. He has worked an independent expert advisor on counter-terrorism at the United Nations and provided recommendations to Member States on best practices on countering the causes of terrorism and its links with organized crime and the implementation of relevant international frameworks in domestic law. Matt has contributed to high-level international conferences and expert group meetings on the subject.

Terrorism and Organised Crime: 

In 2017 Matt co-organised and co-convened a high-level workshop examining the links between terrorism and organised crime with the Royal United Services Institute, Whitehall. 

Matt has recently co-authored a journal article examining the linkages between terrorism and organised crime in the context of Northern Ireland, informed by extensive interviews with law enforcement: Jupp, John and Garrod, Matthew (2019) ‘Legacies of the Troubles: The Links between Organized Crime and Terrorism in Northern Ireland’, Studies in Conflict & Terrorism, DOI: 10.1080/1057610X.2019.1678878. This article is used by the College of Policing.

Matt has published a groundbreaking empirical study of the links between terrorism and organized crime in Africa and the applicability and effectiveness of the African Union's legal instruments in countering this phenomenon. This study further examines the process of how to conduct empirical research on the links between terrorism and organized crime and some of the principal challenges in this regard: M Garrod, ‘The Applicability and Effectiveness of the African Union’s Instruments in Combatting Organized Criminal Terrorism', in IM Rocha, F Seatzu and K Akestoridi (eds), Organized Criminal Terrorism: An International Law and International Relations Perspective (Brill, 2024). 

In October 2024, Matt’s research on ‘The Applicability and Effectiveness of the AU’s Instruments to Organized Criminal Terrorism’ was awarded the Kudos Research Showcase by the publisher (Brill).

Matt is currently co-authoring a monograph entitled Re-thinking the 'Crime-Terrorism Nexus: A Critical Appraisal from a Global Perspective (Routledge).

International Law and Jurisdiction:

Matt has expertise in the international law of jurisdiction and extraterritorial criminal jurisdiction (eg: universal jurisdiction and protective jurisdiction). In this regard, Matt is currently authoring a monograph entitled Extraterritorial Criminal Jurisdiction and International Terrorism: Rethinking the Protective Principle (Hart Publishing) and has recently published two ground-breaking studies on universal jurisdiction. 

The first of these studies provides the first comprehensive empirical analysis of universal jurisdiction in State and treaty practice and sheds new empirical and conceptual clarity on universal jurisdiction and its relationship with jurisdiction in treaty law: Garrod, Matthew (2018) ‘Unravelling the Confused Relationship between Treaty Obligations to Extradite or Prosecute and “Universal Jurisdiction” in the Light of the Habré Case’, Harvard International Law Journal, 59(1), pp. 125-196. ISSN 0017-8063.

The second study challenges existing conventional understandings in doctrine and case law by providing the first comprehensive empirical study of the application of universal jurisdiction in response to surge in Somali piracy between 2006 and 2016 and its comparison with the prosecution of international crimes since the end of World War II to the present day. In so doing, it provides new insight and the first thorough critique of what most scholars, governments, the UN and even the International Court of Justice have said on universal jurisdiction, its purpose and the basis for it in international law: Garrod, Matthew (2019) ‘The Emergence of “Universal Jurisdiction” in Response to Somali Piracy: An Empirically Informed Critique of International Law’s “Paradigmatic” Universal Jurisdiction Crime’, Chinese International Law Journal. DOI: 10.1093/chinesejil/jmz025.

Television appearances:

In 2021, Matt appeared as an expert guest speaker for the documentary series ‘Shadow Worlds: The Global Gangster Network’ produced by ZDF and televised in Austria, Germany, and Switzerland. Matt’s input focused on the links between terrorism and transnational organised crime and the policy, legal and law enforcement responses to this phenomenon by States and by international and regional organisations such as the UN, the AU, and the EU. Matt’s contribution to this series was informed by a new empirical research examining the links between terrorism and organised crime in Africa.

Written evidence:

• 2016: written evidence submitted to an expert study titled ‘In-Depth Analysis: The Application of Universal Jurisdiction in the Fight Against Impunity’, commissioned and funded by the Parliament of the European Union.
• 2017 and 2018: written evidence submitted to the Government of Sri Lanka with respect to ‘Counter Terrorism: A Bill’, published in the Gazette on 17 September 2018.
• 2018: Matt's proposal to codify the law on extraterritorial criminal jurisdiction in the law in England and Wales was shortlisted as a candidate for law reform by the Law Commission.
• 2019: written evidence submitted to the Government of Nigeria in respect of the ‘Terrorism (Prevention and Prohibition) Bill, 2019’, enacted as the ‘Terrorism (Prevention and Prohibition) Act, 2022’, published in Federal Republic of Nigeria Official Gazette on 16 May 2022.
• 2021: written evidence submitted to the South African Government and Department of Police with respect to the ‘Protection of Constitutional Democracy against Terrorist and Related Activities Amendment Bill, 2021’.