The Court of Justice's interaction with the EU legislature in interpreting and applying primary law

The thesis addresses the following question: what is the Court of Justice’s interaction with the EU legislature in interpreting and applying primary law? At first sight, the answer appears rather straightforward. EU legislation is hierarchically subordinate to EU primary law. All the primary law sources – the Treaties, the Charter of Fundamental Rights and so on – constitute, according to the Court’s own words, the ‘constitutional framework’ of the Union. The EU legal order thus possesses a clear normative hierarchy similar to national legal systems, where legislative norms appear subservient to the constitutional norms. In addition, the Court of Justice has been vested by the Treaties with a monopoly to safeguard this hierarchy within the EU legal order, having exclusive jurisdiction to annul EU legislation for violating EU primary law. Therefore, the seemingly straightforward answer to the question posed by the thesis is that the Court of Justice is virtually omnipotent in its interaction with the EU legislature as regards the interpretation and application of primary law.

Nonetheless, even though the Treaties confer on the Court the role to scrutinise the acts of the EU legislature for their compliance with primary law, they are silent on the degree of that scrutiny. Several scholars have already advanced convincing arguments on why the Court should in principle respect the choices of the EU legislature. While, however, this normative argument on how the Court should interact with the EU legislature has been thoroughly articulated in the literature, the same cannot be said of the descriptive assessment of how this interaction has actually unfolded in the Court’s case-law.

The thesis seeks to provide a critical and as comprehensive as possible descriptive analysis of the Court’s case-law. It does so by examining six types of interaction between the Court and the EU legislature in the Court’s case-law: first, the discretion afforded by the Court to the EU legislature when reviewing the validity of EU legislation for its compliance with primary law; second, the Court’s interpretation of EU legislation in the light of primary law, with particular emphasis on cases in which the Court disregards the clear wording of a legislative provision – or, more broadly, the will of the EU legislature – in order to ‘reconcile’ its meaning with primary law; third, the Court’s interpretation and application of primary law in the absence of EU legislation and, in particular, whether the Court takes account of the will of the EU legislature as reflected in the broader legislative framework or in its resistance to Commission’s legislative proposals; fourth, the EU legislature’s power to revise its own assessments by amending legislation, even where that legislation has previously been interpreted and applied by the Court in light of primary law; and fifth, the EU legislature’s power to depart from earlier standalone interpretations of the Court on primary law. These five types of interaction are particularly examined in the fields of internal market integration, fundamental rights protection, EU citizens’ rights and direct taxation.

The main conclusion of the thesis is that the Court’s interaction with the EU legislature is more deferential than what has been generally perceived in the literature.