European Union criminal law as we know it is a product of intensive legal development on both legislative and judicial levels, accompanied by significant changes in the Treaty framework. In this chapter, we will discuss the emergence and nature of harmonisation efforts with an emphasis on especially substantive criminal law. Our claim is that whereas during the Amsterdam era, harmonisation of substantive criminal law was mainly regarded a competence issue, since entering of the Lisbon Treaty together with strengthening of the role of the fundamental rights and human rights in the law of the European Union, the debates concerning European criminal law take place mainly on the level of adjudication. Harmonisation relates not only to the cornerstone principle of mutual recognition but has a link as well to the debates on increased supranationalism as expressed by ‘Taricco saga’ and the establishment of the European Public Prosecutor’s Office.

EU law has increasingly become entangled in difficult and sensitive political questions, which means that studying EU law without appreciating the political context within which it operates risks missing the point. The message of this book, then, is that in studying EU law, the law itself matters as much as context; and context also matters as much as law. This first chapter tackles a question that is at the core of this book: what is the EU for? We will look at four theories that have different answers to the question what the ‘point’ of the EU is: intergovernmentalism, neo-functionalism, supranationalism and post-functionalism. These four theories offer heuristic models to think about the nature of the EU and the choices that are implicit in EU law. As we will see, the tensions, problems and questions discussed in this chapter will resurface throughout the book.

This chapter explores the origins and evolution of supranationality. It contrasts different conceptualizations across various (legal) disciplines by singling out four important contexts which have informed the notion: the turn to modern international law, the establishment of the European Communities, EU law scholarship and the law of IOs. The chapter demonstrates how supranationality is construed through both international law and EU law, which is one of the very reasons its meaning is difficult to pin down. Supranationality, as a doctrinal concept, appears to be trapped by the unresolved quandary of whether EU law is still to be conceived of as being part of international law.

Verdirame argues that liberal internationalism has undergone a largely undetected yet profound transformation in the last decades. As a result of an often unquestioning embrace of the political and legal ideology supranationalism and of globalization, liberal internationalists have slouched towards cosmopolitanism. Yet, cosmopolitanism is a view of the international political order that is at odds with liberal internationalism properly understood. Today’s liberal internationalists, like cosmopolitans, regard world government as both an aspiration and an inevitability. The idea of self-government, which was central to the liberal internationalism of the UN Charter, plays little or no role in this world view. This transformation of liberal internationalism is more evident in Europe, where supranationalism is not merely an ideology but the defining legal and political principle of the EU.