The Principle of Legality as a Pillar of the EU’s Rule of Law: Bridging the Gap between International and National Law

This chapter examines the principle of legality as a central component of the rule of law in the internal context of the European Union (EU), with a particular focus on the perspective of the Court of Justice. It examines the historical development of the principle in the context of modern states and its place in international law. The rule of law is a fundamental concept within the EU's legal and political framework, serving as the cornerstone ensuring that all actions and decisions taken by the EU comply with the principles of legality, transparency, and respect for fundamental rights. Within this comprehensive framework, the principle of legality plays a central role, underlining the need for the exercise of public authority, both at EU and national level, to be clear, predictable, and lawful. The focus on the internal dimension of the rule of law within the EU underlines the crucial importance of ensuring that EU institutions and Member States comply with the legal norms and principles applicable to their respective areas of competence in order to fully affirm a ‘Union based on the rule of law’.