Anatomy of the EU tax list: a case-study on EU external tax policy

Casano, F. (2026)

Doctoral Thesis

Since 2017, the European Union has publicly named non‑EU countries whose corporate tax systems it considers harmful, placing them on a so‑called “blacklist” if they fail reforms. While presented as a neutral and cooperative tool to curb tax avoidance, this list has become one of the EU’s most controversial instruments, extending EU’s regulatory authority beyond its borders.
This dissertation is the first comprehensive study of how the EU tax list works in practice. Through a constructivist framework and on the basis of policymakers interviews, document analysis, and nineteen country case-studies, it examines why the list was created, how it functions, and how targeted countries respond—balancing perspectives and actual experiences from both the EU and developing countries.
Framed as a hybrid governance mechanism combining cooperation, coercion, and reputational pressure, the study finds the EU tax list reflects political compromise more than coherent policy, shaped by competing power struggles within Europe.
Although it greatly revitalises the international debate on tax avoidance, the list’s technical limitations leave significant forms of corporate tax avoidance unaddressed. Listing decisions are inevitably influenced by geopolitical considerations; this creates double standards and undermines its credibility, already weakened by the exclusion of EU Member States with aggressive tax practices from the list. 
Ultimately, the list appears to increasingly serve as a tool of pressure. Its effects are felt strongly in developing countries, many of which are required to adopt rapid reforms they had little role in designing. Faced with tight deadlines, governments often prioritise fast, short‑term compliance over long‑term sustainable change. 
Through a multi-dimensional analysis integrating law, politics, institutional sociology, and international tax governance, this dissertation contributes to shedding light on who benefits and who bears the costs when powerful actors set and impose global tax rules, offering new insights into the political economy of contemporary tax governance and EU institutional change. It challenges dominant narratives of good tax governance by signalling persistent power imbalances between the Global North and South, problematising the legitimacy of imposing EU standards without regard for jurisdictional socio-economic context, and questioning the EU’s self-legitimising rhetoric of fairness. The study also advances theoretical debates on regulatory deterrence and develops a new typological framework for understanding how countries behave under pressure. It offers policy recommendations for a more technically robust, coherent, and equitable EU approach.

• EU tax blacklist
• EU list of non-cooperative tax jurisdictions
• Corporate tax avoidance
• Harmful tax practices
• International tax governance
• External EU governance
• EU regulatory power
• regulatory deterrence
• developing countries
• Global tax justice
• Power and legitimacy

• All authors: Casano, F.
• Supervisor: Streek, J.L. van de
• Co-supervisor: Nouwen, M.F.; Pool, J.M.W.
• Committee: Vleggeert, J.; Apeldoorn, L.C.J. van; Titus, A.; Traversa, E.; Regan, A.
• Qualification: Doctor (dr.)
• Awarding Institution: Institute of Tax Law and Economics, Faculty of Law, Leiden University
• Date: 2026-05-08
• Title of host publication: Meijers-reeks
• ISBN (print): 9789465361093
• Name: MI-462
• Sponsorship: The author was enrolled as a PhD candidate at Leiden University throughout the duration of the project and completed the dissertation under the supervision of academics from Leiden University. Primary funding for this research was provided by Leiden University, supplemented by a grant from the Adessium Foundation to Leiden University. The research was conducted independently; the author has no affiliation or employment relationship with the Adessium Foundation. The author undertook an internship at the European Commission during the PhD trajectory; the internship was unrelated to the research presented in this study.