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BORDERLINES is a Research Group led by Carolyn Moser under the Minerva Fast Track scheme of the Max Planck Society (2019–2022). It explores the governance credentials of key security sectors in Europe—border control, migration management, and cyber resilience—from an interdisciplinary perspective.




The matrix of European security has drastically changed in the last decade. As a result, the ‘borderlines’ of EU security policies are shifting—in terms of space, time, and form. Indeed, EU states increasingly seek to tackle security problems early on and in faraway places, that is before they turn into actual threats, and they often use informal means to do so. These new realities pose, however, a range of governance challenges, such as weak democratic scrutiny, limited judicial review, and incomplete administrative control.

Against this backdrop, the group sets out to disentangle the legal and policy features of European security—principally border control, migration management, and cyber resilience—and seeks to explain how these features (re)configure the law and governance architecture in place. This comprehensive governance investigation rests on an interdisciplinary research design, combining legal analysis with political science research tools.

Photo credit: Dean Hochmann. License: CC BY 2.0

Starting point

The matrix of European security has drastically changed in the last decade. The EU finds itself in an increasingly challenging geopolitical situation. Suffice to mention the fading US commitment to NATO, Russia’s confrontational stance at Europe’s Eastern and Southern borders, Turkey’s ambivalent posture, and China’s assertive foreign policy, including in the EU’s neighbourhood. In addition, many of today’s vital security issues—such as malicious cyber activities, migratory streams, or pandemics—transcend traditional territorial borders and thus render multilateral efforts inevitable.

Key issue

To cope with these novel realities, the EU and its member states have incrementally adapted their laws and politics of security. Three intertwined factors have been key in this development, namely (i) space, (ii) time, and (iii) form. As far as space is concerned, states’ static territorial confines lose their significance, while more fluid and rather functional borders gain traction. Regarding time, we witness a temporal advancement of activities, which echoes the continuously broadening threat perception underpinning security policies. Hence, EU states increasingly seek to tackle security problems early on and in faraway places, that is before they turn into actual threats for EU states. This readjustment also leaves its mark on form, that is the legal and operational methods employed: informality together with a low level of transparency are pivotal to the new EU security matrix.


The reconfiguration of EU security policies, hence, prompts serious governance questions as it leaves us with a highly intricate governance architecture in which democratic scrutiny, judicial review, administrative control, and transparency are largely absent. Although the discrepancy between policy realities and governance requirements is not security specific—many EU policies first expand, while appropriate governance arrangements follow later—the perils deriving from an unsettled governance framework for security matters are particularly grave as security is at the very core of public power.


The objective of borderlines is to explore the evolving governance features of EU security policies. The project hence pursues a three-fold objective: Next to (a) disentangling the new legal and policy features of European security—principally border control, migration management, and cyber resilience—the project seeks to explain (b) how these features (re)configure the governance architecture in place, and (c) to evaluate the governance credentials of the legal and institutional status quo.

Research design

To achieve this three-fold objective, the borderlines project employs an interdisciplinary approach: an in-depth desk study of legal and official sources will be complemented by empirical data (gained through semi-structured interviews) which, in turn, is expected to lead to original conclusions that are of relevance to both legal scholars and political scientists.


The members of the borderlines group have diverse academic backgrounds. This interdisciplinarity, in turn, informs both the approach(es) and output of the research group.

 Dr Carolyn Moser

Dr Carolyn Moser

Head of group

Carolyn is specialized on the Law and Governance of Security and Defence. Trained in both law and political science at Sciences Po Paris and The Fletcher School of Law and Diplomacy (Tufts University, USA), she holds a PhD from Utrecht University, for which she was awarded the Otto Hahn Medal of the Max Planck Society. Her key peer reviewed publications include a prize-winning monograph with OUP on accountability in EU security and defence (2020) and a co-edited book on the legal framework of the OSCE (CUP, 2019).

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 Dr Tarek Tutunji

Dr Tarek Tutunji

Post-doctoral researcher

Tarek Tutunji received his PhD in Political Science in 2019 from Johns Hopkins University with a dissertation on the emergence of informal rules around propaganda and covert action during the Cold War. His research focusses on informal institutions in world politics. He is currently studying the international institution developing around disinformation. He is particularly interested in understanding the emerging European regulatory framework to respond to the malicious manipulation of social media.

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 Felicitas Burst

Felicitas Burst

Research assistant

Felicitas has been studying law at the University of Heidelberg since autumn 2014, with a one-year intermittence at the University of Strasbourg. As a scholarship-holder of the German Academic Scholarship Foundation, she investigated the sociology of law in an interdisciplinary research group led by Prof. Marauhn. Next to her solid knowledge of international law – her major – she enriches the team with practice insights gained through an internship at the Staatsministerium in Stuttgart and her Slavic language skills.

 Lukas Märtin

Lukas Märtin

Research assistant

Lukas has been a law student at the University of Heidelberg since autumn 2017, with 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.

Former team members and affiliates

Rabia Ferahkaya — research assistant (2019–20)
Mohamed R. Abdelsalam — affiliated PhD researcher (2020–21)

Projects (current and past)

  • EU strategic autonomy in the digital realm | collaboration with Moritz Weiss and Felix Biermann (both LMU Munich), workshop and publication in preparation
  • EU strategies to counter digital disinformation and propaganda | publication in preparation
  • The rise of the regulatory security state in Europe | collaboration with Andreas Kruck and Moritz Weiss (both LMU in Munich), special issue in preparation
  • (In)visible frontiers—an interdisciplinary encouter | joint project in preparation with Hana Gründler (KHI Florenz)
  • European integration and the phenomenon of (de-)constitutionalization | joint publication project with Berthold Rittberger, LMU Munich (draft paper in Working Paper format) [completed]
  • The interplay of EU and non-EU norms in the migratory context | cooperation with Mohamed Abdelsalam (Sciences Po Paris) [completed]
  • EU border management and the role of Frontex | Verfassungsblog symposium on 'Frontex—a rising star of declining Europe?' edited by Carolyn Moser, with contributions by Elisabeth Badenhoop, Florin Comad Kund, Rabia Ferahkaya, Samuel Hartwig, Constantin Hruschka, Lukas Märtin, Carolyn Moser, and Catharina Ziebritzki [completed]


  • Moser, Carolyn, Accountability in EU Security and Defence—The Law and Practice of Peacebuilding. Oxford University Press, Oxford, 2020, 336 p. available on OUP website
  • Moser, Carolyn and Berthold Rittberger, 'The CJEU and EU (de-)constitutionalization—unpacking jurisprudential responses', In: International Journal of Constitutional Law, forthcoming, Working Paper version
  • Moser, Carolyn, 'Loin de l’Union, loin des juges?—Sur les voies de recours juridictionnelles dans le cadre des activités de sécurité et de défense extraterritoriales de l’Union européenne', In: Rechtsweggarantie im vergleichenden Verwaltungsrecht, Layla Kristina Jaber, Stefanie Lüer, Anne-Marie Thévenot-Werner (eds.). Schwarze Reihe. Springer, Heidelberg 2021, 215-240. Available as Pre-print version and via Springer online
  • Moser, Carolyn, 'Hard Power Europe?', In: Heidelberg Journal of International Law (HJIL) 1, 1-12 (2020). Open access version
  • Moser, Carolyn, 'Eine kurze Einführung in Frontex'. Newsroom of the Max Planck Society, focus section '25 Years Schengen Area'; updated, enlarged and translated version of the Verfassungsblog post dated 3 February 2020, 20.03.2020.
  • 'Frontex—a rising star of declining Europe?', online symposium on the Verfassungsblog edited by Carolyn Moser
    • Hruschka, Constantin, 'Frontex and the duty to respect and protect human rights',, 07.02.2020
    • Moser, Carolyn, Ferahkaya, Rabia, and Märtin, Lukas, 'Frontex goes Africa: on pre-emptive border control and migration management',, 06.02.2020
    • Coman Kund, Florin, 'The territorial expansion of Frontex operations to third countries: on the recently concluded Status Agreements in the Western Balkans and beyond…',, 06.02.2020
    • Ziebritzki, Catharina, 'Refugee camps at EU external borders, the question of the Union’s responsibility, and the potential of EU public liability law',, 05.02.2020
    • Badenhoop, Elisabeth, 'Contextualising Frontex: A Long-Term Perspective on Database Monitoring of Migrants',, 04.02.2020
    • Hartwig, Samuel, 'Quo Vadis Frontex: Crossing the Fine Line Between Prevention and Repression?', 04.02.2020.
    • Moser, Carolyn, 'A very short introduction to Frontex—unravelling the trajectory of one of the EU’s key actors', 03.02.3020. 
  • Moser, Carolyn, 'Accountability in a multi-jurisdictional order', In: Controlling EU Agencies. The Rule of Law in a Multi-jurisdictional Legal Order, Mira Scholten, Alex Brenninkmeijer (eds.). Edward Elgar, Cheltenham 2020, 60-79 (with Gijs Jan Brandsma). EE website
  • Moser, Carolyn, 'Integrating Contrasting Approaches: Civil–Military Cooperation in CSDP'. PeaceLab, 07.01.2020.
  • Moser, Carolyn, 'Frieden durch Recht aus französischer Perspektive' in Jäger S. and Heinz, W. (eds), Frieden durch Recht. Rechtstraditionen und Verortungen (Springer, 2020) SpringerLink
  • Moser, Carolyn, 'Two Become One? On the Civil–Military Amalgamation of the CSDP'., 30.03.2019. 

Outreach and media appearances

  • Global (dis)order and International Law | Carolyn Moser discusses with Carlo Masala (Bundeswehr University, Munich), Anne Peters (MPIL) and Christian Marxsen (MPIL) the legal and political parameters of German foreign and security policy, and the challenges ahead. A video of the panel discussion held on 21 September is available on the MPIL's Youtube channel (own input starting at 29'20)
  • Unpacking the significance of the Solidarity Clause for EU disaster relief | Carolyn Moser gives a keynote speech at the Interparliamentary Conference for the CFSP/CSDP on the panel 'Capability Development for the EU’s Civil Protection and the Solidarity Clause: Integrating the Military'. A video recording of the talk given on 9 September 2021 is available here (at 2'20)
  • Europe and its migration and border management | Carolyn Moser speaks with the Swiss Broadcasting Corporation (SRF) on migration, border control and in particular Frontex, streamed on 3 June 2021 and available as podcast
  • Unsere fremden Grenzen. Europas Türsteher am Rande der Sahara | Carolyn Moser as interviewee for radio feature (in German language) by Christian Jakob, RBB Kultur, 16 December 2020, audio recording
  • Grenzenlos? Vom Recht und Kontext der EU-Sicherheitspolitik | Talk (in German language) given by Carolyn Moser online in the context of a lecture cycle on migration and refugee law of the Refugee Law Clinic Würzburg e.V., University of Würzburg (D), 9 December 2020

Conference papers and presentations

  • Moser, Carolyn, Border realities in times of Covid-19, discussant of Ayelet Shachar's book 'The Shifting Border' (2020) at the ISA 2021 Annual Convention, April 2021
  • Moser, Carolyn & Rittberger, Berthold, The (de-)constitutionalization of EU security policies, commentary in the context of the workshop 'The transnational politics of emergencies', WZB, Berlin, June 2020
  • Moser, Carolyn, The External Dimension of EU Migration Control—A Security Perspective, invited talk at a conference of the Research Initiative on Migration of the Max Planck Society 'The Challenges of Migration and Integration', Munich, 17 June 2019
  • Moser, Carolyn, Lifting Pooling and Sharing to a Higher Level: The European Air Transport Command, presentation given at the 3rd Annual Conference of the European Initiative on Security Studies (EISS), Sciences Po, Paris, 27 June 2019
  • Moser, Carolyn, From safe distance to de facto convergence—Revisiting the civil-military nexus in EU security and defence, presentation at the workshop 'The European Union’s "New Defence Policy": European Military Integration in an Interdisciplinary Perspective', Justus Liebig Universität, Gießen, 18 January 2019