Photo of Professor Thomas Horsley

Professor Thomas Horsley LL.B (Hons), LL.M, PhD (Edinburgh)

Professor of Constitutional Law Law


Personal Statement

Thomas is a Professor of Constitutional Law. He was Associate Head of Department from 2019-2022 and Director of Postgraduate Research from 2014-2017. Thomas is Subject-Editor of the Oxford Encyclopaedia of European Law (2021-) and Review Editor for the European Law Review (2020-).

Thomas specialises in constitutional and comparative law with a particular focus on the UK and EU legal systems. His research expertise also covers the Court of Justice of the EU; constitutional theory; and EU internal market law, including the free movement of capital. He is currently PI on a UK in a Changing Europe funded project investigating the impact of the United Kingdom Internal Market Act 2020 on Welsh Law (awarded Sept. 2023).

Thomas has published widely in leading international journals and edited collections (see here for details). His monograph, 'The Court of Justice of the European Union as an Institutional Actor: Judicial Lawmaking and its Limits' (preview here), was published by Cambridge University Press in 2018. His most recent work, and future research agenda, is focussed on exploring the conceptual foundations of the UK constitution (eg Legal Studies, 2022), the impact of the UK's withdrawal from the EU on the UK constitution and the comparative constitutional study of legal transplants (eg Oxford Journal of Legal Studies, 2022).

Thomas regularly contributes expert reaction to national and international media (incl. BBC One Politics; BBC News; CTV News Canada; UK in a Changing Europe) on major legal developments on EU and UK constitutional law. His monograph on the Court of Justice also featured in the London Review of Books (7 January 2021). He has previously received invitations to present to the European Parliament's EPP Group on the challenges of Brexit for the UK constitution and to contribute expert evidence to the House of Lords EU Select Committee. He also acted as UK rapporteur at the XXVI FIDE Congress hosted by the University of Copenhagen for the topic "Union Citizenship: Development, Impact and Challenges."

Thomas has supervised a number of PhD projects to completion, including theses on the hierarchy of norms in EU integration and the constitutional position of national parliaments in the EU legal order post-Lisbon. He welcomes enquires from prospective students with proposals on topics related to UK and EU constitutional law, comparative constitutional law and legal transplants.

Prizes or Honours

  • Invited to attend Judicial and Academic Visit, Court of Justice of the European Union (2017)
  • Author of the "Legal Developments" contribution for the Journal of Common Market Studies Annual Review (2014)
  • Doctoral Award (2009-2011) (Arts and Humanities Research Council, 2009)
  • Research Preparation Master's Award (2007-2008) (Arts and Humanities Research Council, 2008)

Funded Fellowships

  • Fellow of the Institute of Advanced Studies (Hebrew University of Jerusalem, 2019)