I am Professor of Public International Law at the University of Bristol. Previously, I held positions at the John W Kluge Center, Library of Congress, Washington DC, and the Universities of Oxford and Reading.

My research interests cut across a number of topics within public international law, with recent work focusing on international dispute settlement, international humanitarian law, international human rights law and international criminal law. I was awarded a 2023 Philip Leverhulme Prize in Law for the international impact of my research. My monograph, Detention in Non-International Armed Conflict, which was published in 2016 by Oxford University Press, was awarded the American Society of International Law's 2016 Francis Lieber Prize for best book in the field of international law and armed conflict as well as the 11th Paul Reuter Prize (administered by the International Committee of the Red Cross). It was also shortlisted for the SLS Peter Birks Book Prize for Outstanding Legal Scholarship. My scholarship has been cited by, amongst others, the UK Court of Appeal and UK Supreme Court.

I work with policymakers and practitioners on various issues in international law and have acted as advisor to, inter alia, United Nations Special Rapporteurs, the International Bar Association, the European Parliament, and the UK Ministry of Defence. I frequently deliver lectures to government and military lawyers, and I assist counsel in cases raising public law and public international law issues before UK courts and before international tribunals. I have been Called to the Bar of England & Wales.

I often work with the media on issues related to armed conflict, including for the BBC, New York Times, DW, and CNN.