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The BORDERLINES Research Group (active 2019–22) explored the governance credentials of two different, but both central transboundary security phenomena in Europe—namely border control and migration management, on the one hand, and cyber security and the question of disinformation, on the other—from an interdisciplinary perspective. It was led by Carolyn Moser under the Minerva Fast Track scheme of the Max Planck Society.


In a nutshell

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.

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.

Against this backdrop, the Borderlines group disentangled the evolving governance features of transboundary European security phenomena—in particupar border control, migration management, and disinformation in the cyber realm—and identified how these features (re)configured the law and governance architecture in place. This comprehensive governance investigation rested on an interdisciplinary research design, combining legal analysis with political science research tools.


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

  • Dr Carolyn Moser, Head of group (2019-22)
  • Dr Tarek Tutunji, Post-doctoral researcher (2020-22)
  • Felicitas Burst, Research assistant (2020-22)
  • Rabia Ferahkaya, Research Assistant (2019-20)
  • Lukas Märtin, Research assistant (2019-22)
  • Mohamed R. Abdelsalam, affiliated PhD researcher (2020-21)

Select output and activities


  • Moser, Carolyn & Berthold Rittberger, 'The CJEU and EU (de-)constitutionalization—unpacking jurisprudential responses', In: International Journal of Constitutional Law, forthcoming, Working Paper version
  • Moser, Carolyn & Blockmans, Steven, 'The extent of the European Parliament’s competence in Common Security and Defence Policy', in-depth analysis requested by the SEDE sub-committee of the European Parliament, 2022 (with Steven Blockmans). open access version Pdf of the study (PDF, 914.2 KB)
  • 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, 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, 'Hard Power Europe?', In: Heidelberg Journal of International Law (HJIL) 1, 1-12 (2020). Open access version
  • 'Frontex—a rising star of declining Europe?', online symposium on the Verfassungsblog dealing with EU border management and the increasing role of Frontex, 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


  • Beyond Borders. Franco-German experiences during the pandemic | Carolyn Moser takes part in a panel discussion on border control and (free) movement during times of health emergencies, Karlsruhe, 26 April 2022
  • The possible use of the EU's Mutual Assistance Clause in the face of new threats—legal background and implications under international and European law | Carolyn Moser speaks as an invited expert at a Public Hearing at the European Parliament (SEDE subcommittee), Brussels, 29 November 2021
  • 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 2021 is available on the MPIL's Youtube channel (own input starting at 29'20)
  • 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

Media appearances

  • 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

Conference papers and presentations

  • Moser, Carolyn & Tutunji, Tarek, The EU's fight against disinformation and the war in Ukraine, joint talk at the MPIL, Heidelberg, 20 June 2022
  • 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
  • Tutunji, Tarek, The Digital Services Act (DSA) and Digital Markets Act (DMA), presentation at the MPIL, Heidelberg, 22 March 2021
  • Moser, Carolyn, The EU strikes back? On the imposition of the first ever sanctions against cyber-attacks, presentation at the MPIL, Heidelberg, 14 September 2020
  • 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