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European security revisited (ENSURE)

The law and governance of European security in a new geopolitical era

ENSURE (European security revisited) is a Max Planck Research Group headed by Dr Carolyn Moser and funded by the Max Planck Society (2022-27). It explores and critically assesses the – potentially significant – reshaping of law and governance triggered by the European Union's normative and policy adjustment to increasingly harsh geopolitical realities.

About the group

  • KEY ISSUE. European security is currently undergoing massive upheaval, not least since the war in Ukraine. In response to these profound geopolitical changes, the law and governance of security and defence in Europe are being adapted, in some cases very extensively, to meet the new realities.
  • PURPOSE. The objective of the ENSURE research group is to investigate and critically assess the (potentially significant) changes in law and governance triggered by this geopolitical adjustment. Changes may relate to European and national actors and their prerogatives, decision-making and regulatory modalities, financial arrangements and industrial support, international cooperation and partnerships, or strategic objectives and political means.
  • QUESTION. Against this backdrop, ENSURE aims to provide a response to the pressing question: what law and governance for European security in a new geopolitical era? To answer this question, the group (i) examines whether and how the EU’s legal and institutional architecture needs to be adapted to the new geopolitical realities, and (ii) seeks to determine whether and how this adaptation can take place while reconciling constitutional norms and security interests.
  • THEMES. The research of ENSURE unfolds along three interrelated strands of research:
    • Conceptual and strategic foundations. Under this theme, the group investigates and interrogates concepts, (legal) principles, and strategic considerations that shape European security policies and activities.
    • Actors and accountability. This strand of research deals with the reconfiguration of the legal and institutional framework of European security, which is currently in a state of flux.
    • Regulatory modalities and policy instruments. Specific (new) challenges require appropriate normative solutions and policy tools. Hence, recalibrating legal and policy instruments to face the geopolitical realities of the 21st century is the focus of the third research area.
  • RESEARCH DESIGN. The comprehensive legal and governance analysis is based on an interdisciplinary research design (legal analysis combined with political science research tools) that allows exploration of both the theory and practice of European security. Indeed, a thorough desk study of legal and para-legal sources, as well as their discussion and contextualization in the academic literature, is embedded in a broader theoretical framework, which in turn is complemented by empirical findings obtained through qualitative research methods (i.e., semi-structured interviews).


ENSURE has 10 team members, all of whom contribute to the success of the project. In addition, several affiliated researchers enrich the group with their expertise.

 Dr Carolyn Moser

Dr Carolyn Moser, Research Group Leader

Dr Carolyn Moser leads the ENSURE group, in parallel to holding the Alfred Grosser Chair at Sciences Po Paris. She conducts research in the field of international and European law and governance, with a special focus on security and defence in Europe. Carolyn was trained in both law and political science at Sciences Po Paris and The Fletcher School of Law and Diplomacy (Tufts University, USA), and holds a PhD from Utrecht University on EU civilian crisis management. She received several awards and distinctions for her research, notably the Otto-Hahn-Medal and the European Court of Auditors Award. Her interdisciplinary expertise is solicited also beyond academic circles, for instance by EU and international institutions (eg European Parliament; OSCE; World Bank) and in the media (eg AFP; Deutschlandfunk; Libération; NDR; ORF; SRF). A full list of her publications can be found here.

 Rocío Bargon Sánchez

Rocío Bargon Sánchez, Administrative & Language Assistant

As an administrative and language assistant, Rocío Bargon Sánchez supports the ENSURE team with her linguistic skills, cultural competences, and organizational know-how. She holds a Double Master's Degree in specialised translation and multimedia translation from the Johannes Gutenberg University and the University of Burgundy. Before joining the group, Rocío taught German as a Foreign Language and worked as a freelance translator and subtitler. Within the framework of a Bluebook traineeship at the Directorate-General for translation of the EC, Rocío had the opportunity to become part of one of the biggest translation services in the world. Her working languages are German, Spanish, French, English, and occasionally Portuguese.

 Laurids Hempel

Laurids Hempel, Research Assistant

Laurids Hempel reinforces the group as a research assistant. He has been studying law at the University of Heidelberg since 2018, including two semesters abroad at the University of Montpellier, where he focused on studies in international public law and constitutional law. The latter is also his major in his law studies. Following his fascination for politics and public law, he has already worked for one year in the Schleswig-Holsteinischer Landtag (State Parliament of Schleswig-Holstein) before beginning his studies. With his legal knowledge and insights gained into political decision-making processes, he is eager to assist the research of the group at the interface of international public law, European law, and national public law.

 Dr Kerttuli Lingenfelter

Dr Kerttuli Lingenfelter, Senior Research Fellow

Dr Kerttuli Lingenfelter, a postdoctoral researcher joining ENSURE in January 2024, specializes in the international law of crime and critical approaches to international law. Her research will focus on European law and policy regarding extraterritorial criminal jurisdiction. Kerttuli studied at Tallinn University and the European University Institute, where she defended her PhD thesis on the legal and affective dimensions of international criminalization. She has held visiting researcher positions at Vrije Universiteit Amsterdam, at the Eric Castrén Institute of the University of Helsinki, and editorial positions at the European Journal of International Law and the European Journal of Legal Studies.

 Lukas Märtin

Lukas Märtin, Doctoral Candidate

Lukas Märtin contributes to the group's research as a doctoral candidate. He studied law in Heidelberg and did a one-year study abroad period at Sciences Po Paris. Motivated by his strong interest in European and international law, he interned at the European Parliament, in the cabinet of Advocate General Juliane Kokott at the CJEU and, moreover, reached the final round of pleadings of the renowned European Law Moot Court Competition in his role as Advocate General. Hence, he joins the team with useful practice insights into the law and governance of EU institutions and processes.

 Chiara Miśkowiec

Chiara Miśkowiec, Student Assistant

Chiara Miśkowiec joined the group as a student assistant. She has been studying law at the University of Heidelberg since November 2020 and spent the summer semester 2023 at the Jagiellonian University in Kraków. During her time abroad, she focused on the study of constitutional law and EU law. With the insights gained from her studies in Poland, she is now eager to continue her studies in Heidelberg with a focus on international law and to contribute to the ENSURE team with her language skills and her knowledge of Eastern European culture and history.

 Finn Preiß

Finn Preiß, Research Assistant

Finn Preiss comes to the group as a research assistant, having studied law at the University of Heidelberg since 2019, with a focus on public international law. He deepened his knowledge of international and European law during an exchange year at the University of Paris 1 Panthéon-Sorbonne. Following his interest in political decision-making, he completed an internship at the German Federal Ministry of the Environment. As security issues have aroused his interest, he is looking forward to supporting the group.

 Effi Spiegel

Effi Spiegel, Research Assistant

Effi Spiegel supports the group as a student assistant. She has been studying law at the University of Heidelberg since 2019. In 2021, she spent a year at the University of Paris 1 Panthéon-Sorbonne, where she mainly followed courses on European law. Inspired by her academic experience in Paris, she interned at the German Ministry of Finance's Directorate-General for European Policies and at the Brussels office of a German law firm. Moreover, she is regularly involved in Model European Union projects, where she has been developing a particular interest in European security. She is therefore excited to build upon her so far established experience in an interdisciplinary context.

 Dr Christian Schultheiss

Dr Christian Schultheiss, Senior Research Fellow

Dr Christian Schultheiss is an ENSURE Senior Research Fellow. His research has specialized in ocean governance, conflict and maritime security with a focus on Asia. He conducts research on European security in the maritime domain. He was trained in International Relations and in International Law and holds a PhD in Political Science from the University of Cambridge. He has had several field research positions in China, Japan, the Philippines and Singapore. He has been a policy advisor for the European External Action Service and advised the EEAS on a range of EU policy initiatives in the area of maritime security.  His publications appeared in International Relations and in International Law outlets.

 Dr Sofia Vandenbosch

Dr Sofia Vandenbosch, Senior Research Fellow

Dr Sofia Vandenbosch will join the Group in January 2024. She is a recognized expert in the field of constitutional comparison and human rights protection, and formerly worked for two years as a legal advisor at the Belgian Ministry of Foreign Affairs and as a lecturer at UCLouvain. Sofia studied law and European affairs in Belgium (Liège, Leuven, Ghent) as well as in Glasgow and defended her doctoral thesis on the Europeanisation of treaty-making power at UCLouvain.

Former team members and affiliates

Anne Marie Thévenot-Werner—affiliated researcher, Paris 2; previously visiting researcher (July 2023)

Dr Nina Boy—affiliated researcher; previously visiting senior researcher (2023)

Jule Sommer—intern (2023)

Felicitas Burst—research assistant (2022–23)

Dr Tarek Tutunji—affiliated researcher, former staff member (2019–21)




  • Lukas Märtin (together with Carl Mühlbach), Katalysator der Polykrise: Das Staatsschuldenrecht und seine verfassungsgerichtliche Überprüfung als Hindernis politischer Gestaltungskraft, VerfBlog (blogpost), 24th November 2023
  • Lukas Märtin, The EU Terror List and the Islamic Revolutionary Guard Corps: About the Law as an Alleged Obstacle to Political Action, Max Planck Institute for Comparative Public Law & International Law (MPIL) Research Paper No. 2023–22 (SSRN), October 2023
  • Carolyn Moser, The Concept of Accountability. In: Research Handbook on the Accountability for Human Rights Violations: What, Who, What For, How, To What Extent, Michelle Duin & Kristin Henrard (ed.), Edward Elgar (forthcoming 2024).
  • Christian Schultheiß, What has China's Lawfare Achieved in the South China Sea? In: Perspective, Yusof Ishak Institute, N° 51 (journal article), 1–9, July 2023.
  • Carolyn Moser, Die Zeitenwende: viel Zeit, wenig Wende? In: Zeitschrift für ausländisches öffentliches Recht und Völkerrecht 4 (comment), 741–768, 2022.
  • Carolyn Moser, Some reflections on anticipatory governance in EU defence. In: Foresight and regulation: anticipatory governance and administrative foresight in times of transition and recovery (book section),165–190, 2023. Updated and enlarged version of this piece is available as an open-access contribution to the MPIL Research Paper Series (research paper).
  • Christian Schultheiss, La Chine et les limites conceptuelles et pratiques de la guerre juridique en mer de Chine méridionale. In: Revue Défense Nationale 852 (book section), December 2022.
  • Carolyn Moser, The war in Ukraine and its repercussions on Europe's security and defence constitution (blogpost), September 2022.
  • Carolyn Moser & Berthold Rittberger, The CJEU and EU (de-)constitutionalization—unpacking jurisprudential responses. In: International Journal of Constitutional Law (journal article), 20(3), July 2022.
  • Carolyn Moser & Steven Blockmans, The extent of the European Parliament’s competence in Common Security and Defence Policy (study), June 2022.
  • Carolyn Moser & Estelle Hoorickx, The EU mutual assistance clause, and its applicability to novel threats (e-Note; English; French), June 2022.
  • Carolyn Moser, Is Berlin's overdue defence policy adjustment also a "game changer" for Franco-German relations? (blogpost), March 2022.


  • Christian Schultheiß participates in the panel discussions on the "Maritime Security Challenges and the quest for greater domain awareness in the Indo-Pacific" during the 3rd SHARE.IT conference at the UNODC Regional Office for Southeast Asia and the Pacific in Bankok, Thailand between the 22nd and the 24th November 2023.
  • Carolyn Moser inputs her expertise as a pannelist in the public debate entitled “Der Deutsche Bundestag und vernetzte Auslandseinsätze – Welche Verantwortung und Kontrollmöglichkeiten hat das Parlament?“, organized by the 1st Committee of Inquiry (Afghanistan) in the 20th electoral term of the German Bundestag, taking place at the Paul-Löbe-Haus in Berlin on 14th November 2023 (video recording; 01:29:10).
  • Invited by the Foreign Service Institute of the Philippines, Christian Schultheiss gives a presentation on "The impact of the Arbitral Award of 2016 seven years hence" at the Dialogue on Governance in the South China Sea, 16th-12th August 2023.
  • Guest speaker and affiliated researcher (Paris 2), Anne Marie Thévenot-Werner, inaugurates the first session of the ENSURE Colloquium with a lecture on, “The Immunity of International Organizations and Their Officials in War Zones,” at the Max Planck Institute for Comparative Public Law and International Law in Heidelberg, 12th July 2023.
  • Carolyn Moser participates in the Trier Talks on Law and Digitalisation lecture series, delivering a presentation on the topic of Cyberwarfare titled “Hackbacks – eine europarechtliche Perspektive” at the Law Faculty of the University of Trier, 6th June 2023 (further information).
  • Nina Boy contributes to the workshop 'Beyond paradigms: Tim Sinclair's social foundations of global finance' with the presentation 'Sovereign safety revisited' at the University of Warwick, 27th June 2023.
  • Nina Boy gives a presentation on Security Capitalism: Risk without return at the Symposium Crises Capitalism: Shadow banking, central banks, and new configurations of state-financial market entanglements at the Convention Center Schloss Herrenhausen in Hannover, 7–9 June 2023.
  • Christian Schultheiss participates in the first trans-regional Steering Committee Meeting of IORIS, a Maritime Domain Awareness and information-sharing platform for maritime law enforcement agencies and navies in Bali, Indonesia, 24th and 25th May 2023 (further information).
  • Carolyn Moser delivers a keynote speech on EU security and defence after the Russian invasion of Ukraine: a legal-institutional perspective at the Academy of International Affairs NRW in Bonn, 15th May 2023 (further information).
  • Christian Schultheiss speaks about the United Nations Convention on the Law of the Sea (UNCLOS) and more specifically The maritime dispute settlement and security in the Indo-Pacific, at the European Security and Defence College seminar for officials of Indo-Pacific countries and the EU in Brussels, 4th May 2023.
  • As part of the Lecture Series Ukraine, Carolyn Moser gives a presentation on The European Security Architecture in the Light of New Geopolitical Realities at the Württembergische Landesbibliothek (WLB), 3rd May 2023 (video recording).
  • Nina Boy participates in a panel discussion on The Situation and its Truth at the Workshop Situational Awareness: Sensing Insecurity and Coming Catastrophe, University of Hamburg, 27–28 April 2023.
  • Carolyn Moser holds a presentation on The EU's Common Security and Defence Policy. Status quo and challenges in view of the war in Ukraine at The XXII Walter Hallstein-Symposium “The Common Security and Defence Policy of the EU – Perspectives from Member States” at the Goethe University in Frankfurt, 30th and 31st March 2023 (further information).
  • Carolyn Moser discusses Accountability in EU Security and Defence at the Award ceremony for the 2020 and 2022 ECA Awards for research on public-sector auditing in Luxemburg, 23rd March 2023 (further information).
  • Carolyn Moser provides experts insights into The Common Security and Defence Policy after the Russian invasion of Ukraine at the webinar on EU Law and Politics after the Russian Invasion organized by UKAEL and the Finnish branch of FIDE, 21st March 2023 (further information).
  • Carolyn Moser gives a presentation on "The Ukrainian War, a Reality Check for International Law" at the Amnesty International Members Conference in Mannheim, 19th February 2023.
  • Carolyn Moser participates as an expert in a Panel discussion in the context of the 'Europa Quartett' hosted by the Heinrich Böll Stiftung in Bremen, together with Dr. Helga Trüpel, Dr. Emanuel Herold and Madita Standke-Erdmann, 12th February 2023 (further information).
  • Christian Schultheiss chairs the panel discussions of the 4th ASEAN Regional Forum (ARF) Workshop on the Law of the Sea Convention (UNCLOS) in Hanoi, 30th November to 1st December 2022 (media mention).
  • Christian Schultheiss presents Maritime Security Challenges in ASEAN at the 2nd EU-IDFR Diplomacy Course 2022: 45 Years of ASEAN-EU Relations and the Road Ahead in Malaysia, 26th – 28th October 2022 (detailed programme).
  • Carolyn Moser holds a lecture on the EU and the War in Ukraine at the annual meeting of the Deutsche Vereinigung für Internationales Recht (DVIR), the German branch of the International Law Association (ILA) in Frankfurt a.M., 18th November 2022.


  • Course aux armements : les États-Unis raflent la mise.
    Carolyn Moser provides expert insights to Karina Chabour in the TV programme 'La semaine de l'éco', broadcasted by France 24 on 17th November 2023. Available as video recording (in French language)
  • Un avis d'extradition envoyé par courrier aux ressortissants ukrainiens en Irlande ? C'est faux.
    Carolyn Moser gives expert input on the potential extradition of Ukrainian citizens by Ireland to Agence France-Presse (AFP). Published in an online article on 18th September 2023.
  • La guerre en Ukraine a-t-elle fait exploser l'Europe de la Défense ?
    Carolyn Moser gives an expert interview to Bastien Boname for the French online magazine C'actus.
  • Les touristes russes n’ont-ils vraiment plus le droit de venir en Europe avec une voiture ou un téléphone ?
    Carolyn Moser shares expert insights into the legal aspects of the recent European sanctions imposed on Russia, particularly regarding the potential impact on Russian citizens travelling to the European Union with the French news service Libération. Published in an online article on 14th September 2023.
  • VerfassungsPod #3: Verfassung im Krieg
    Carolyn Moser provides input as an expert to the podcast of Jochen Schlenk and Maximilian Steinbeis on the rules and regulations regarding German (and European) defence, available here.
  • Zeitenwende in Europa
    Carolyn Moser gives an expert interview to Julia Weigelt (NDR) about the geopolitical awakening of Europe and the EU in the wake of the Russian war on Ukraine for the NDR Info Podcast "Streitkräfte und Strategien" (armed forces and strategies), broadcasted on 19th September 2022, available here (in German language).