We live in fast times: reviewing in summer 2022 a book on the European Union published in January of the same year means reading a piece that did not have the chance to include a crisis in its reflections that is of fundamental relevance for – besides humanitarian issues and global geopolitical implications, of course – questions of European Integration: the Russian invasion in Ukraine. It is in the context of the war that normative questions ranging from democratic principles to issues of energy distribution become very crucial (again) at the European agenda. In light of this, it is even more welcome that the book “Flexible Europe. Differentiated Integration, Fairness and Democracy” by Richard Bellamy, Sandra Kröger and Marta Lorimer goes much beyond the technocratic perspectives on the EU that have dominated EU studies for some time, and engages in questions of normative foundations of and political divisions in Europe. Providing fundamental reflections on the normative and democratic foundations of the EU, the book is a very timely and inspiring companion for scholars of European Integration and EU citizens interested in the future of the Union alike.

The book is divided into two parts. In the introduction, which precedes these two parts, the authors first provide an overview on both parts and lay the foundations for their case for differential integration (DI). Bellamy, Kröger and Lorimer distinguish between different forms of DI. Drawing on Thomas Winzen (2016), they first differentiate between ‘capacity DI’ and ‘sovereignty DI’. Capacity DI refers to a differential integration process rooting in different capacities (e.g. administrative or financial) of member states – or in the assumption that some member states might have different capacities than others. This might result in a ‘multi-speed Europe’, with some member states integrating faster than others. Sovereignty DI, on the other hand, matters in the context of core state power transfer to the European level when ideological or pragmatic reasons keep member states from fully joining treaties or policy transfers (as the authors state, Euroscepticism can be a reason, but also stem cell research or abortion debates in a member state). This has been called ‘Europe à la carte’. Departing from the general idea of sovereignty DI, the authors add a further dimension of DI, which they discuss in greater detail further down the book: ‘value DI’. Value DI refers to a form of differential integration that does not only allow for member states voluntarily opting out from certain integration steps, but also for exclusion of member states in the case of democratic backsliding.

DI in general – be it sovereignty DI, capacity DI or value DI – is, in the eyes of the authors, not a failure of European integration or a pragmatic solution for a limited period of time, but “functionally necessary [and] normatively desirable given the ineliminable diversity and pluralism of any Union as large as the EU” (p. 11). Establishing a format for a ‘flexible Europe’ that allows for DI whenever it is (functionally or normatively) necessary is for Bellamy, Kröger and Lorimer a fundamental democratic arrangement tailored to the needs of the European Union as a pluralist entity. Their perspective is a ‘demoicratic’ one: it views the EU as a union of states with different state peoples, or demoi. In contrast to accounts that view European Integration as a pathway towards a European society with a European people and a European democracy, in the demoicratic approach, the EU is seen as “supplementing rather than supplanting the domestic democratic systems of the member states, so as to facilitate their mutual cooperation. The result is a system whereby the peoples of Europe can ‘govern together but not as one’” (p. 11).

Making a case for differential integration from a democratic – or, more precisely, from a demoicratic – perspective, the authors argue that any implementation of DI needs to be morally justified. This necessity for moral justification is, as they underline, not only rooted in the EU’s liberal foundations that are laid down in the Treaties (justice, equality, democracy, the rule of law, pluralism, diversity etc.), it is also a functional necessity for the political procedures. DI that is perceived as unfair and undemocratic “will not generate the support it needs to work” and “fail its purpose of reconciling member states that want to integrate to different degrees, and at different speeds.” (pp. 14-15). Hence, DI requires normative foundations that can be shared by all European peoples (respectively by their representatives).

The claim for a (demoicratic) normative foundation of DI is the bottom line for the book’s philosophically very thorough first part, titled Normative Perspectives on Differentiated Integration. To lay theoretical foundations for their normative take on DI, the authors here present a very stimulating normative yardstick for assessing DI in general. For the development of their normative criteria, they draw on John Rawls’ reflections on fairness among different state peoples (i.e. national cooperation in an intergovernmentalist manner) and among citizens of a state (i.e. a supranational, cosmopolitan perspective). After discussing criteria of political – or procedural – fairness, and social justice – or substantive fairness – stepwise for both the intergovernmentalist and the supranational facets of the EU, demoicracy is then presented as an opportunity to combine intergovernmentalist and supranational claims of justice and fairness.

As “an international association involves a contract between both state peoples and the individual citizens of the association”, a demoicratic EU would “combine[…] the statist and cosmopolitan perspective” (p. 43). The practical challenge, however, lies in combining procedural and substantive fairness supranationally between state peoples and transnationally between individual citizens. Here, Bellamy, Kröger and Lorimer suggest that DI is a normatively and functionally well-suited solution, as it can help “fostering a Union in which member states can simultaneously meet their obligations to their own people” (p. 48). While in situations when “groups of citizens are heterogenous and have unequal stakes in a collective decision” capacity DI would apply, sovereignty DI comes to play when “groups have heterogeneous public cultures and feel they belong to distinct demoi” (p. 67). In addition, value DI becomes a crucial tool – this is elaborated in the final chapter of the first part of the book – in the case of democratic backsliding of some member states. When the fundamental principles in Article 2 (respect for human dignity, freedom, democracy, equality, the rule of law and respect for human rights) are considered as foundational demo(i)cratic features of the EU, opting out from these Article 2 principles would be beyond legitimate DI even in a demoicratic scheme. Hence, if member states violate the principles, this could result in a form of ‘reduced cooperation’ based on a lack of capacity to meet one or more of the three minimal requirements for a functioning constitutional democracy” (p. 84). In practical terms, the authors refer to conditionality with regard to EU funding and the withdrawal of voting rights in the Council.

In its second part, titled Political Party Perspectives on Differentiated Integration, the book then turns towards the views of political party actors on DI; a fundamental dimension of the political legitimacy of a demoicratic perspective on DI. Departing from existing research’s findings, the authors present very insightful own empirical material they gained from 35 semi-structured interviews with party actors from Austria, Denmark, Germany, Greece, Hungary, Portugal and Romania (all parties in these countries were contacted that scored above 5 per cent in the most recent national and EU elections). The chapters that report the findings provide very interesting insights into perceptions of the different forms of DI, and on the challenges with regard to fairness. Often, DI is seen as a functional tool for European Integration, but not a normative desirable one. Furthermore, respondents repeatedly point to practical trade-offs between procedural and substantive fairness in the implementation of DI.

However, the most relevant finding is, in the eyes of the reviewer and seemingly also of the authors, the fact that a cleavage appears between richer and poorer countries with regard to the support of DI: “Indeed, most respondents who opposed DI had experience of it, and came primarily from poorer countries in Southern and Central and Eastern Europe. These opponents expressed concerns that DI might negatively affect their position within the Union, resulting in them being left outside the core of European integration against their will” (p. 105). Democracy – be it supranational democracy, national democracy, or a European demoicracy – requires equality, and equality requires fair distribution of resources and chances. What is more, affected actors – states people and citizens – need to perceive the system and its procedures as fair; otherwise legitimacy is withdrawn. This is true for input and output legitimacy, but in the case of DI probably even more for throughput legitimacy (i.e. the quality of the governance process itself; Schmidt, 2103). The reported fears of the interviewees from poorer countries that DI might leave them behind clearly points to the relevance of such throughput legitimacy, and it might also prove a point for approaches advocating for greater redistribution among member states (see the authors’ discussion on p. 47). Widening the redistributive tools of the EU, both with regard to a supranational (i.e. cohesion funding) and a cosmopolitan (e.g. individual level social protection) dimension might thus increase the legitimacy – input, throughput and output legitimacy – of the European Union as such, particularly if well aligned with the different variants of DI that are so well spelled out in this timely and inspiring book.

On a side note, it is slightly ironic that reviewing the book was indeed a little impeded by outcomes of what might be perceived as failed demoicratic DI. As post-Brexit tax rules made it costly to receive in Germany a hard copy of the book produced in the UK, I preferred to work with the digital version. The e-book was very accessible and good to read; however, its content menu is poorly structured and the reader has to refer to the table of contents at the beginning of the book constantly – though this does not by any means hamper the pleasant experience of reading the inspiring book, which was also a great stimulus to re-think questions of legitimacy and democracy in Europe. The book is rich in normative reflections and empirical insights, and I look forward to future research linking its findings to further theoretical and empirical work. Here, particularly a link to the cosmopolitan side of the demoicracy coin, which was deliberately left out from the book, would be of great interest. How citizens perceive differential integration and how this is linked to their views on EU democracy and the legitimacy of the European project will be a fascinating avenue for future research for which this book provides an excellent basis.