The project examines the role of courts in the EU. It focuses on the often neglected impact of cross-level judicial control on the horizontal separation of powers, i.e. the balance of competences between the legislative, executive and judicial branches.
While one of the core tasks of the judiciary is to keep checks and balances within a constitutional system, the particularity of the development to be explored lies in the cross-level interplay between competence and control: national courts claim stronger control over the exercise of competence at the European level in order to contain a feared loss of competence at the national level, but also to re-balance the horizontal distribution of power at EU level. If a national court, such as the German Federal Constitutional Court, claims to review whether an EU institution has exceeded its competences, it may at the same time demand a re-balancing of competences between the EU institutions, for example, the reduction of the independence of the European Central Bank. Conversely, the ECJ increasingly monitors the exercise of competences at the national level and sometimes directly addresses the structure of national institutions. If the ECJ enforces the judicial independence of national courts as a response to national rule-of-law crises, it essentially demands a re-balancing of competences at the national level.
The project has three main thrusts. First, it aims to produce the first comprehensive study of comparative constitutional law on how national constitutional and supreme courts exert a controlling influence on the horizontal power-sharing at EU level. Secondly, it will produce the first in-depth legal study of whether and to what extent the ECJ may influence the domestic structure of powers, including the legislative and executive branches. Thirdly, the project will examine from an overall perspective whether there are regulative principles that apply to cross-level and value-based judicial control, whereby for the first time the principle of equality of member states will be the focus of an in-depth study.