The European Court of Justice and the Judicialization of EU Governance

For their part, social scientists have produced more research on the ECJ, and its impact on markets and politics, than on any other court in the world, with the single exception of the United States Supreme Court. This article concentrates on three dimensions of the ECJ’s impact. First, blending quantitative and qualitative methods, scholars have conclusively demonstrated that the legal system exerted decisive influence on market and political integration in Europe, pushing the project further and faster than the Member States had been prepared to go on their own. As ultimately constructed, the courts proved to be effective mechanisms for enforcing the property rights of transnational actors, especially those engaged in cross-border trade, and for monitoring Member State compliance with both the Treaty and secondary law (EC statutes). Second, a large body of empirical research, mostly in the form of descriptive case studies, has documented the ECJ’s pervasive influence on outcomes in a diverse range of policy domains. Today, no student of EU politics can afford to ignore the role of the judiciary, the impact of which can be crucial. Third, political scientists and academic lawyers have collaborated in research on the Europeanization of national law: the impact of EU law, including the ECJ’s case law (its jurisprudence), on national legal systems. Conceived broadly, these topics overlap a wide range of issues covered by other contributions to the Living Reviews in EU Governance series, including integration theory, Europeanization, multi-level regulation and governance, and the evolution of the EU’s institutional arrangements. The article proceeds as follows. In Section 1, I define the concepts of judicialization and governance, and discuss how they are related. The “constitutionalization of the EU,” and its effect on EU governance, is one of the most complex and dramatic examples of judicialization. Section 2 considers the institutional determinants of judicial authority in the EU. As we will see, these determinants are not fixed, but rather have evolved as constitutionalization has proceeded, which makes the overall system difficult or impossible to model in any rigorous, formal way. I then review the literature on the relationship between the courts and EU governance, focusing on the three dimensions of impact just noted. Section 3 examines the impact of the European Court of Justice, and of the legal system it manages, on the overall course of integration. In Section 4, I discuss the judicialization of the policy process, focusing on the influence of the ECJ’s case law – its jurisprudence – on the decision-making of non-judicial actors (e.g., the Commission, the Council of Ministers, the Parliament). Section 5 considers the role of courts in monitoring and enforcing Member State compliance with EU law, and the extent to which these activities have provoked the Europeanization of national law and policymaking