Contact John Cubbon:

Telephone +44 20 3984 6244


24Hr Emergency No.: +44 7935 302030

John Cubbon | Guernica 37

John Cubbon joined Guernica 37 International Justice Chambers in 2021. He is an international lawyer with many years’ experience of criminal justice issues arising in fragile and conflict-affected states. After practising at the Bar of England and Wales in crime, employment and immigration, he held legal positions in the United Nations for 19 years and since 2015 he has undertaken assignments for the Stabilisation Unit as a Deployable Civilian Expert.

John has a firm grounding in international humanitarian law and international criminal law. For nine years he held senior legal positions in Chambers at the International Criminal Tribunal for the former Yugoslavia (ICTY), where his main focus was on the preparation of draft judgements, decisions and orders and memoranda on points of law and factual analysis. As a Deployable Civilian Expert he advised and trained members of the Malian Armed Forces on international humanitarian law.


Since 1996 John has frequently contributed to judicial reform, legislative drafting and institutional development. He was extensively engaged in the reform of criminal legislation in both Bosnia and Herzegovina and Kosovo. To a large extent this involved ensuring compatibility with the European Convention on Human Rights. Shortly after the establishment of UNMIK he had a managerial role in the re-establishment of the prosecutorial and judicial system in Kosovo. He has also worked on reform of the justice sector in Bosnia and Herzegovina, Ukraine and the Occupied Palestinian Territories. 


At a time when the UN Interim Administration in Kosovo had an executive mandate he performed a range of functions in criminal justice that government lawyers would ordinarily be responsible for. These concerned such matters as extradition and international legal assistance as well as sensitive individual cases often involving human rights. 


John has taught adults for 40 years in a considerable variety of contexts.  As well as training the Malian military, he has given seminars and lectures on international criminal law, for example during his nine years at ICTY. From 2014 to 2017 he taught part-time on the Masters degree in Security, Conflict and International Development at the University of Leicester. 


From 2017 until 2020 he was a member of the Drafting Committee of the Human Rights Committee of the Bar of England and Wales. Since 2020 he has acted as a pro bono consultant for the Truth, Reconciliation and National Unity Commission of Seychelles.


John has been admitted to the Lists of Counsel and Assistants to Counsel at the International Criminal Court and the List of Counsel (Defence/Victims) at the Kosovo Special Chambers. Since November 2019 he has been a member of the Council of Europe panel of international experts on legislation in the criminal justice area in Ukraine.

Areas of Expertise

Extradition and Mutual Legal Assistance

Rule of Law Development

Government Advisory Work

Public International law 

Atrocity Crime Prevention

International Criminal Law



French (working knowledge)

Bosnian/Croatian/Serbian (reading ability)

Albanian (reading ability)