This chapter examines the European Union’s justice and home affairs (JHA), which have evolved from a peripheral aspect into a focal point of European integration and today are at the centre of politicization in the EU. It first considers the institutionalization of JHA cooperation and its gradual move towards more supranational competences before discussing political contestation as expressed in the context of Brexit and the crisis of the common asylum and Schengen systems. The development of cooperation is retraced, looking at the main actors in the JHA, the organization and capacities of EU institutions, the continuity of intergovernmentalism, the proliferation of semi-autonomous agencies and databases, and the flow of policy, taking into account asylum policy and immigration policy, police and judicial cooperation in criminal matters, and the challenge of implementation. The chapter shows how the gradual move of cooperation among national agencies concerned with combating crime; fighting terrorism; and managing borders, immigration, and asylum from loose intergovernmental cooperation to more supranational governance within the EU has remained contested, and argues that this contestation exemplifies the limits of political unification.
