Pre-Emption in EU Law

Pre-emption in EU law refers to the process by which EU action displaces or limits the power of Member States to legislate or act in a given field. The concept operates within the framework of EU competence — the distribution of powers between the Union and the Member States — and determines the legal effects of the exercise of Union competence on the residual competence of Member States. Pre-emption is not a single rule but a set of doctrines that vary according to the nature of the competence involved and the degree to which the Union has exercised its legislative power. The concept is essential to understanding the federal character of the EU legal order and the boundaries of national legislative autonomy.

Types of Competence and Pre-Emptive Effect

The Treaty of Lisbon codified the categories of EU competence in Articles 2–6 TFEU, which determine the scope and effect of pre-emption.

Exclusive competence (Article 2(1) TFEU): in areas where the Union has exclusive competence — the customs union, competition rules necessary for the functioning of the internal market, monetary policy for euro area Member States, conservation of marine biological resources under the Common Fisheries Policy, and common commercial policy — only the Union may legislate and adopt legally binding acts. Member States may act only if empowered by the Union or to implement Union acts. Pre-emption in exclusive competence is automatic: the Member States’ power to act is displaced regardless of whether the Union has actually legislated.

Shared competence (Article 2(2) TFEU): in areas of shared competence — including the internal market, social policy, economic and social cohesion, agriculture, environment, consumer protection, transport, energy, and the Area of Freedom, Security and Justice — both the Union and the Member States may legislate. Member States may exercise their competence to the extent that the Union has not exercised its competence. Once the Union exercises its competence, Member States are pre-empted from acting in the area covered by the Union measure. However, the pre-emptive effect is limited to the specific field regulated by the Union act, not the whole policy area.

The key issue in shared competence is the scope of pre-emption: how much national regulatory freedom remains after the Union has acted. The answer depends on the nature of the Union measure, its objectives, and the degree of harmonisation it achieves.

Pre-Emptive and Non-Pre-Emptive Shared Competence

The Court of Justice has distinguished between pre-emptive shared competence (where Union action exhaustively occupies the field) and non-pre-emptive shared competence (where Union action sets minimum standards or leaves room for national variation). The distinction reflects the degree of harmonisation intended by the Union legislature.

In areas where the EU adopts maximum harmonisation measures — typically regulations or fully harmonising directives — Member States may not maintain or introduce provisions that deviate from the EU rules, even where those provisions are more protective of the relevant public interest. The Commission’s Tobacco Advertising I judgment (Germany v Parliament and Council, Case C-376/98) illustrated that where the EU adopts a measure based on internal market competence, the measure may displace divergent national rules to ensure the smooth functioning of the market.

In areas where the EU adopts minimum harmonisation measures — common in social policy, environment, and consumer protection — Member States may maintain or introduce more stringent protective measures, provided such measures are compatible with the Treaties and, where applicable, notified to the Commission. Minimum harmonisation provisions in directives typically include explicit “claw-back” clauses preserving national competence to adopt stricter standards.

The ERTA Effect

The ERTA doctrine (Commission v Council, Case 22/70) establishes that where the Union adopts common rules in a given area, Member States may not enter into international commitments that affect those rules or alter their scope. The ERTA effect operates as a form of pre-emption in the external sphere: internal Union legislation may generate implied external competence that pre-empts Member State action in international negotiations.

The Court clarified the scope of ERTA pre-emption in Opinion 2/91 concerning ILO Convention No 170 on chemicals safety, in Commission v Denmark (the Open Skies cases, Cases C-466/98 to C-469/98), and in Commission v Greece (Case 45/07). The principle is now codified in Article 3(2) TFEU, which provides that the Union has exclusive competence for the conclusion of an international agreement where its conclusion is provided for in a legislative act of the Union, is necessary to enable the Union to exercise its internal competence, or affects common rules or alters their scope.

The Lotito Cases and Pre-Emption of National Procedural Rules

The Lotito family of cases addresses pre-emption in the context of national procedural rules that impede the effective enforcement of EU law. In Simmenthal (Case 106/77), the Court held that national courts must set aside national procedural rules that prevent them from giving immediate effect to EU law. In Factortame (Case C-213/89), the Court required national courts to grant interim relief against national legislation alleged to violate EU law, pre-empting national procedural rules that prohibited such relief.

The pre-emptive effect in these cases is not based on the Union having exercised legislative competence in the field of civil procedure. Rather, it flows from the requirement of effective judicial protection — derived from Article 19 TEU and Article 47 of the Charter — which pre-empts national procedural rules that would make the enforcement of EU law rights impossible or excessively difficult. This form of pre-emption is functional rather than sectoral: it does not remove the area of civil procedure from national competence but limits the exercise of that competence where it would impair the effectiveness of EU law.

Relationship with Subsidiarity and Proportionality

Pre-emption is moderated by the principles of subsidiarity and proportionality. Subsidiarity (Article 5(3) TEU) constrains the Union from acting in areas of shared competence where the objectives of the proposed action can be sufficiently achieved by the Member States. Where the Union does act, proportionality (Article 5(4) TEU) requires that the content and form of Union action not exceed what is necessary. The Protocol on the Application of the Principles of Subsidiarity and Proportionality requires the Commission to provide detailed justifications for the pre-emptive effects of proposed legislation.