Chapters

The Internal Market: An International Perspective

in Oxford Principles of European Union Law: Volume II – The Internal Market, ed. Schütze & Tridimas (Oxford University Press, 2026)

Summary: The creation of a common market has been at the heart of the European integration process since the establishment of the European Economic Community in 1957; and it remains central to the European Union today. Building on the first volume of the Oxford Principles of European Law, this treatise provides a systematic analysis of the legal principles governing the establishment and functioning of the EU internal market. Spanning thirty-six chapters, Volume II: The Internal Market thus brings together distinguished academics and practitioners to analyse all aspects of the EU internal market. Part I explores the history and nature of the EU internal market, focusing on international, historical, comparative, and constitutional perspectives. Part II and Part III examine the free movement of goods, both as regards the general rules setting the tone for EU market integration at large as well as its special rules on important policy areas, such as the Common Agricultural Policy. Part IV explores the free movement of persons and Part V discusses the freedom of services and the free movement of capital. Part VI looks at positive integration through Union harmonization and private standard setting. Finally, Part VII deals with the 'external' aspects of the EU internal market and discusses the extent to which the Union has widened its market to non-Member States. Completely up to date with the most recent case law, this book will be invaluable to academics and practitioners in EU and international economic law.

The Internal Market: A Constitutional Perspective

In Oxford Principles of European Union Law: Volume II – The Internal Market, ed. Schütze & Tridimas (Oxford University Press, 2026)

Comparative International Law: A Historical Reconstruction

In Comparative International Law, ed. Schütze & Siems (Hart, 2026)
Pages 27-48

Die Mitgliedstaaten als Glieder der Union: Artikel 4

in Europäisches Verfassungsrecht (3. Auflage), ed. J. Bast & A. von Bogdandy.
Pages 565-605
Beck, 2025

Introduction

In EU Landmark Cases, ed. Craig & Schütze (Oxford University Press, 2025)

Future(s) of the Union: Some Thoughts after Brexit

In A Multilevel Constitutional Perspective on Brexit: From Local to Global, ed. C. Fasone & C. Martinelli (Giappichelli, 2023)
Pages 119-130

Fiscal Barriers in the Internal Market

In EU Fiscal Federalism: Past, Present, Future, ed. Alicia Hinarejos and Robert Schütze (Oxford University Press, 2023)
Pages 11-30

Le domaine des compétence d'execution

In Traité de droit Administratif Européen, ed. Jean-Bernard Auby & Jacqueline Dutheil de la Rochère (Bruylant, 2022)
Pages 75-92

From Dassonville to Cassis: The Revolution that did not Take Place

In Cassis de Dijon: 40 Years On, ed. Albertina Albors-Llorens, Catherine Barnard & Brigitte Leucht (Hart, 2021)
Pages 23-42

Modelli di "demoi-crazia": l'Europa e la sua Unione

In Parlamenti e democrazia in Europa, ed. Fasone, Lupo, and Vauchez (il Mulino, 2020)
Pages 77-126

Foreign Affairs Federalism in the European Union

In Oxford Handbook of Comparative Foreign Relations Law, by Curtis Bradley (Oxford University Press, 2019)
Pages 333-351

Summary: The European Union was born as an international organization. The 1957 Treaty of Rome formed part of international law, although the European Court of Justice was eager to emphasize that the Union constitutes “a new legal order” of international law. With time, this new legal order has indeed evolved into a true “federation of States.” Yet how would the foreign affairs powers of this new supranational entity be divided? Would the European Union gradually replace the member states, or would it preserve their distinct and diverse foreign affairs voices? In the past sixty years, the Union has indeed significantly sharpened its foreign affairs powers. While still based on the idea that it has no plenary power, the Union’s external competences have expanded dramatically, and today it is hard to identify a nucleus of exclusive foreign affairs powers reserved for the member states. There are, however, moments when both the Union and its states enjoy overlapping foreign affairs powers. For these situations, the Union legal order has devised a number of cooperative mechanisms to safeguard a degree of “unity” in the external actions of the Union.

Third Country Goods in the EU Internal Market

In The Law of the EU Internal Market and the Future of European Integration, ed. Amtenbrink, Davies, Kochenov & Lindeboom (Cambridge University Press, 2019)
Pages 200-214

Summary: With regard to third country goods, the EU Treaties had chosen a seemingly simple rule. Founded on the idea of a customs union, they decreed that – unlike in a free trade area – third country goods were simply assimilated to Member State goods once they had lawfully entered the common market. From the very start, Article 28 TFEU thereby stated that the provisions on the elimination of customs duties as well as the prohibition of quantitative restrictions “shall apply to products originating in Member States and to products coming from third countries which are in free circulation in Member States”. The idea behind the provision was straightforward: while direct exports into the Union would, constitutionally, not enjoy free movement rights, once a third country good had crossed the Union’s customs barriers, it was entitled to circulate freely within the internal market. Indirect imports of third-country goods from one Member State to another were consequently protected under European Union law, and in particular: Articles 30 and 34 TFEU. But would both provisions apply in the very same way, and to the same extent, to third country goods once in free circulation? And when exactly would goods be considered in “free circulation”? This small contribution discusses these issues.

Constitutionalism(s)

In Cambridge Companion to Comparative Constitutional Law, ed. Roger Masterman & Robert Schütze (Cambridge University Press, 2019)
Pages 40-66

Summary: Constitutionalism is the set of ideas that defines what a constitution is or ought to be. For some, there exists an essential core meaning of the term; while for others, the concepts of ‘constitution’ and ‘constitutionalism’ have fundamentally changed over time. Various conceptions of constitutionalism have indeed developed in legal history. The various ‘constitutionalisms’, and their relations to each other will be discussed in this chapter. The most prevailing element of any constitutional theory in the past three hundred years has thereby been the link between the idea of a constitution and that of the modern (unitary) state. Yet as Section 4 hopes to show, the state-centred idea of a constitution cannot explain federal unions, such as the (early) United States or today’s European Union, in which there are two levels of government making a constitutional claim over the same people(s).

The ‘Unsettled’ Eighteenth Century: Kant and his Predecessors

In Globalisation and Governance: International Problems, European Solutions, ed. Robert Schütze (Cambridge University Press, 2018)
Pages 11-40

Summary: With the decline of the (inter)national idea of “empire” in the early modern period, the belief in a “universal” law binding all humanity was gradually replaced by legal pluralism. The apostles of State sovereignty came to deny the very existence of supranational legal authority above the State and introduce a distinction that still structures our modern imagination: the distinction between national and international law. What are the normative foundations of modern international law? The question gained prominence in the seventeenth and eighteenth centuries, in which three – contrasting – common topoi co-exist. The first reaches back to a (metaphysical) world republic that “authorizes” all positive international law; the second conception grounds international law solely in the consent of sovereign States, while a third conception defends the idea of “civil law” between States through a federal foundation. The most sophisticated combination of all three conceptions has emerged in the writings of Immanuel Kant. Originally disregarded as a legal philosopher, Kant’s ideas on the foundations of (inter)national law have re-gained enormous importance in the twentieth century.

Introduction

In The United Kingdom and the Federal Idea, ed. Robert Schütze & Stephen Tierney (Hart, 2018)
Pages 1-26

Summary: The first part of this introduction explores the “internal” and “external” (quasi-)federal structures within the United Kingdom through the prism of six constitutional questions. The association and integration of Scotland emerges as a first constitutional question in the seventeenth century (1). The Irish “question” would occupy much of the eighteenth and nineteenth centuries (2). Within the twentieth century, finally, the past processes of incorporation were complemented by a process of legislative devolution that has created “regional” legislatures and governments (3). Externally, by contrast, the “American question” would lead to a fall of the first British Empire (4). In the future British Commonwealth, the “dominion question” would nonetheless be posed (5); and that Commonwealth would also, in the twentieth century, need to respond to the “European question” (6). Having looked at these six questions, the second part of this introductory chapter explores the uneasy relationship between “sovereignty” and “federalism” in British constitutional law discourse.

Direct Effects and Indirect Effects of Union Law

In Oxford Principles of European Union Law - Volume I: The European Union Legal Order, ed. Robert Schütze & Takis Tridimas (Oxford University Press, 2018)
Pages 265-299

Summary: Would the Union legal order insist on a monist relationship for all European law, or only for some of it? And what would this mean for the doctrine(s) of (in)direct effect? This Chapter explores these questions in five sections. Section 2 analyses the general principles governing the direct effect of European law, such as the conditions and dimensions of the doctrine, while Section 3 explores some special rules applicable to “ordinary” (direct) Union law. Sections 4 and 5 will subsequently focus on two special secondary sources of European law: directives and international agreements. The former originally appeared to be the “international” law instrument of the Union that would – as such – be incapable of producing direct effects in the national legal orders. International agreements, by contrast, constitute an external source of Union law and the problem therefore arises whether the principles developed in the Union’s internal sphere apply, mutatis mutandis, to its external sphere. Section 6 will finally look at the various indirect effects that Union law can have on national and – other – European law. We shall see there that the doctrine of indirect effect holistically complements and interacts with the doctrine of direct effect.

Political Philosophy of Federalism

In Max Planck Encyclopedia of Comparative Constitutional Law, ed. Wolfrum, Rüdiger, Grote, Rainer & Lachenmann, Frauke (2017)

Summary: This is an Oxford/Max Planck Encyclopaedia entry on the political meaning of federalism that was last updated in 2023…

EU Competences: Existence and Exercise

In Oxford Handbook of European Union Law, ed. Anthony Arnull & Damian Chalmers (Oxford University Press, 2015)
Pages 75-102

Summary: What constitutional principles govern Union competences? Article 5 TEU identifies three constitutional principles: conferral; subsidiarity; and proportionality. The principle of conferral concerns the (limited) existence of Union competences. These competences are limited in two ways. Quantitatively, they will be confined by a—limited—material scope; qualitatively, they might be limited to a particular type of intervention. In contrast to the principle of conferral, the principles of subsidiarity and proportionality do not concern the existence of legal competence but only limit its exercise. According to the principle of subsidiarity, the Union must show that it is better able to solve a social problem than the Member States; whereas the proportionality principle generally insists that Union action must not exceed what it necessary to achieve a Union objective. This chapter analyses each of the three constitutional principles governing Union competences and the conceptual relations between them.

Classifying EU Competences: German Constitutional Lessons?

in The Division of Competences between the EU and the Member States, ed. Sacha Garben and Inge Govaere.
Pages 33-58
Hart Publishing, 2017

Constitutionalism and the European Union

In European Union Law, ed. Catherine & Steve Peers (Oxford University Press, 2014)
Pages 71-96

Summary: This chapter addresses the question of whether the EU has a constitution. This question has plagued EU law ever since its birth. The chapter explores the formal constitutionalist credentials of the Union legal order and shows that the Union has claimed that the EU Treaties constitute the highest law in Europe. It then examines the constitutional nature of the Union from a ‘democratic’ perspective. Finally, it evaluates the Union legal order through the lens of liberal constitutionalism. This ‘classic’ constitutionalism assesses the legal nature of a document by insisting on a separation of powers and the existence of fundamental rights.

External Union Policies: An Overview

In Foreign Affairs and the EU Constitution, ed. Robert Schütze (Cambridge University Press, 2014)
Pages 407-481

Summary: An updated version of this chapter can now be found in my “European Union Law” (Oxford University Press, 2025)…

The "Treaty Power" and Parliamentary Democracy: Comparative Perspectives

In Foreign Affairs and the EU Constitution, ed. Robert Schütze (Cambridge University Press, 2014)
Pages 359-406

Summary: Foreign affairs are historically non-parliamentary affairs. The right to wage war and to make peace were traditionally seen as part of the royal prerogative. And since the treaty power was perceived as an appendage to the right of war, it was ‘naturally’ considered to belong to the executive branch. This reasoning seems much less persuasive today than several hundred years ago. The question today is ‘no longer whether or not to involve the people or their representatives in the conduct of foreign affairs, but rather if there are any absolute limits – in the interest of the State – to this democratic evolution’ (de Visscher). What are these constitutional limits; and what are their underlying reasons? And, in particular, how democratic is the treaty power in the United States and the European Union? Section 1 starts with an analysis of the American constitutional order and its solutions to international treaty-making. Section 2 moves to the European treaty power. The final section compares the democratic credentials of the American and European treaty power, and thereby draws a variety of conclusions.

Limits to the Harmonization Power of the Union

In The EU as a Federal Order of Competences, ed. Loïc Azoulai (Oxford University Press, 2014)
Pages 215-233

Summary: This chapter examines the internal market competence of the United States and the EU. It first considers the American internal market competence — the ‘Commerce Clause’ which allows Congress to regulate Commerce in several states and has been the chief competence to deregulate and re-regulate the American federal market. It then analyses the EU's internal market competence, showing that Article 114 TFEU has — like the US ‘Commerce Clause’ — been given an (almost) unlimited scope. Both the American and the European internal market powers have encountered some political and legal limits, and the chapter compares these constitutional limitations.

Federalism as Constitutional Pluralism: Letter from America

In Constitutional Pluralism in the European Union and Beyond, ed. Mattej Avbelj & Jan Kommarek (Hart, 2011)
Pages 185-211

Summary: What can a “Letter from America” offer to European constitutionalism? Europe’s constitutional tradition continues to insist on the idea of undivided sovereignty. This poses – unsolvable – problems for an analysis of the political and constitutional dualism that characterizes the European Union. For a tradition that relies on the – unitary – concept of sovereignty, constitutional pluralism must be seen as a “novelty” or “aberration”. The absence of an “Archimedean point” from which all legal authority can be explain is here – wrongly – hailed as a sui generis quality of the European Union. So, why not see the normative ambivalence surrounding the supremacy principle in the European Union as part and parcel of Europe’s federal nature? This chapter looks at four constitutional conflicts in the history of the United States – two before and two after the Civil War. It shows that even American postbellum constitutionalism would not lead to the (European) idea of national sovereignty. American constitutionalism thus continues to subscribe to the idea of divided sovereignty, and thus: constitutional pluralism. Federalism = constitutional pluralism.

European Union, Decision-Making and Competences on International Law Issues

In Max Planck Encyclopedia of Public International Law - Volume III, ed. Wolfrum, Rüdiger, Guhr, Alexandra, Heilmann, Daniel, Kaiser, Karen, Lachenmann, Frauke, Pohlmann, Monika & Reuss, Matthias (Oxford University Press, 2011)
Pages 814-822

Summary: This is a Max Planck Encyclopaedia entry on EU external relations law …

European Union, Party to International Agreements

Summary: This is another Max Planck Encyclopaedia entry on EU external relations law …

Introduction

In The European Union and Global Emergencies, ed. A. Antoniadis, Robert Schütze & E. Spaventa (Hart Publishing, 2011)
Pages 1-7

Summary: By and large, modern societies face three major types of crisis: political, such as wars or rebellions; or natural disasters, such as floods or earthquakes; or economic, a type of emergency which has become more prominent in contemporary society. How should a legal order deal with such emergencies? Two constitutional options are possible: a ‘relativist’ or an ‘absolutist’ approach. The ‘relativist’ approach accepts that the ordinary constitutional principles may not apply in emergency situations and can be suspended in times of crisis. This approach has informed German constitutional thought. By contrast, the ‘absolutist’ approach has informed the United States of America. It considers the constitution as a ‘law for all seasons’ … The Union legal is posited nearer the ‘absolutist’ constitutional approach, yet it is not absolutely ‘absolutist’. It offers a variety of constitutional and legislative tools to deal with internal or external emergencies. This book deals with these tools. It is divided into three parts: Constitutional Challenges (Part I); Thematic Challenges (Part II); and The Perspective of the Institutions (Part III). Part I analyses the basic parameters of the Union constitutional framework in dealing with global emergencies. Part II deals with the specific contexts, such as armed conflict, terrorism, the financial and debt crisis, energy security and food safety, within which the Union emergency constitution has been tested and developed. Part III gives the perspective of the Union institutions and provides a practical flavour on how constitutional and substantive policy considerations are taken into account by those who handle such emergencies on a daily basis.

Constitutional Limits to Delegated Powers

In The European Union and Global Emergencies, ed. A. Antoniadis, Robert Schütze & E. Spaventa (Hart, 2011)
Pages 49-70

Summary: Is there a non-delegation doctrine in the European legal order? May the Union legislator delegate wide regulatory powers to the Union executive? Are there constitutional limits to delegated powers; and if so, will these limits depend on the identity of the delegee? This chapter wishes to answer these questions in three sections. Section 2 investigates the constitutional limits to delegations of power to two European institutions: the Commission and the Council. Section 3 analyses the (non)delegation doctrine in relation to ‘bodies other than those which the Treaty has established’. We will see here that the European Court established strict substantive limits on delegating powers to European Agencies and has limited delegations of powers to international bodies by emphasizing the need for political control mechanisms. Section 5 finally looks at the possibility of delegating powers back to the Member States. Next to a general delegation doctrine within the Union’s exclusive powers, a specific form of emergency delegation emerged here in situations of a ‘dysfunctional’ Union legislator.

Die Verfassung der "Vereinigten Staaten von Amerika": Föderalismus als (Inter)nationale Ordnung

in Europäischer Föderalismus im Licht der Verfassungsgeschichte, ed. Thomas Bruha (Liechtensteinische Akademische Gessellschaft, 2011)
Pages 83-116

Summary: This is the German-language version of my earlier (English) work on the American tradition of federalism as a mixed format that stands on the “middle ground” between international and national law and in which constitutional conflicts are likely to occur…

The "Succession Doctrine" and the European Union

In A Constitutional Order of States: essays in EU law in honour of Alan Dashwood, ed. Arnull, Anthony, Barnard, Catherine, Dougan, Michael & Spaventa, Eleanor (Hart, 2011)
Pages 459-484

Summary: The law of succession represents one of the unruliest parts of international law. Should a new subject of international law be bound by the old obligations of its ‘predecessor’? Two theories exist in classic international law to provide answers to this problem. The ‘continuity theory’ insists on the continuity of sovereignty that passes—with all rights and obligations—from the old to the new subject of international law. The theory thus protects the validity of obligations assumed under international treaties. The ‘clean slate’ theory, by contrast, emerges out of the ‘subjectivist’ philosophy of the nineteenth century. The view denies succession: sovereignty cannot be transferred from a ‘predecessor’ to a ‘successor’. This second view has—with one (or two) exception(s) —become the dominant philosophy in the twentieth century. Would international law apply this solution to treaty successions within unions of states? When states unite they may create a new subject of international law. Should we view this phenomenon in terms of succession? And, if so, should the union start with a ‘clean slate’; or, should it be bound by the international agreements of its Member States? This chapter looks for answers to these questions in the context of the European Union.

Federalism and Foreign Affairs: Mixity as an (Inter)national Phenomenon

In Mixed Agreements Revisited, ed. Christophe Hillion & Panos Koutrakos (Hart, 2010)
Pages 57-86

Summary: In federations, there are then potentially two governments that could potentially engage in foreign affairs. Yet, despite the internal division of power, classic international law responded to the emergence of federal States ‘by ignoring their constitutional characteristics and assimilating them to other sovereign States’. This blind spot of classic international law resulted from two foundational principles. According to the doctrine of sovereign equality, all subjects of international law were sovereign States. Formal equality meant that any division of powers within a federal State could not affect its external appearance on the international scene. The federal State was—as a State—sovereign under international law. The federal principle would here be reduced to an internal phenomenon that would structure the constitutional relations between the two governments. And as a constitutional principle of domestic law it could have no international import. This followed from the second foundational principle: the doctrine of dualism. But could the member states of a federation still conclude international treaties? Section II of this contribution will offer comparative constitutional perspectives from the United States of America (and Canada) as well as Germany (and Belgium). We shall contrast the American tradition of the ‘ closed’ federal State with the European tradition of the ‘open’ federal State. In section III we shall analyse the solutions adopted by the European Union that will be identified as an ‘open’ federation.

On 'Middle Ground': The European Community and Public International Law

In Highest Courts and the Internationalisation of Law: Challenges and Changes, ed. Sam Muller & Marc Loth (Hague Academic Press, 2009)
Pages 35-73

Summary: Does the Community legal order constitute a closed 'self-contained regime' or will it be an 'open system'? While founded on the basis of an international treaty, the European Community still had to determine - not unlike national legal orders - the effects of public international law in its 'domestic' sphere. Has the Community legal order thus assumed an 'autonomous' position vis-à-vis general international law? And if so, what is the status and effect of international norms in the Community legal order? This chapter discusses these issues by analysing the constitutional regime developed for international treaties concluded by the Community and customary international law. The second part changes perspective and investigates when the Community has considered itself materially bound by international agreements concluded by its Member States via the doctrine of functional succession. In general, the Community's constitutional choice vis-à-vis public international law has a federal dimension: placed on systemic middle ground', the EC legal order may potentially operate as a conduit for the incorporation of international law in the national legal orders of its Member States.

The European Community's Federal Order of Competences: A Retrospective Analysis

In 50 Years of the European Treaties: Looking Back and Thinking Forward, ed. Michael Dougan & Samantha Currie (Hart, 2009)
Pages 63-92

Summary: Each legal base within the Treaty is characterised by three dimensions: competence, instrument and procedure. The three parameters determine the degree of legal ‘power’ enjoyed by the Union. This chapter analyses the first dimension of legal power. The federal quality of this dimension emerged in the Union legal order after the European Court of Justice declared that the Community enjoyed ‘real powers stemming from a limitation of sovereignty or a transfer of powers from the States to the [Union], the Member States have limited their sovereign rights, albeit within limited fields, and have thus created a body of law which binds both their nationals and themselves’ (Costa v ENEL). But what was the nature of these ‘real powers’? Would their nature reveal the ‘essence’ of the Union? Were there, perhaps, different types of federal power? This chapter will explore the various competence formats that have emerged, actually or rhetorically, in the European legal order in the past 50 years.