## Facts

- The European Court of Justice (ECJ) delivered a judgment in Case 106/77, commonly referred to as _Simmenthal II_.
- The case concerned the relationship between European Union (EU) law (then European Community law) and the national laws of Member States.
- It specifically addressed the duties and powers of national courts when faced with a conflict between a provision of directly applicable EU law and a provision of their own national legislation.
- The ruling built upon earlier ECJ jurisprudence, particularly Case 6/64, _Costa v ENEL_, which had established the principle of the supremacy of EU law.
- The judgment is rooted in the objective of the Treaty of Rome to create a uniform and effective legal order applicable across all Member States.

## Issues

1. What is the full extent of a national court's obligation to give immediate effect to directly applicable provisions of EU law where they conflict with provisions of national law?
2. Is a national court, faced with a conflict between EU law and national law, required to await the formal repeal or annulment of the conflicting national law by a national legislative body or a higher national court before applying the EU law provision?
3. Does the obligation to disapply conflicting national law apply regardless of whether the national law was enacted before or after the relevant EU law provision came into force?
4. Does the obligation to ensure the primacy of EU law apply uniformly to all national courts, irrespective of their position within the national judicial hierarchy or any national procedural rules to the contrary?

## Decision

- The ECJ ruled that national courts have a duty to give immediate and full effect to provisions of EU law, and this duty requires them to disapply any conflicting provision of current or future national law.
- National courts must not wait for the conflicting national law to be set aside by a legislative act, a constitutional court, or any other national authority before applying EU law; they must do so themselves in the proceedings before them.
- This obligation applies to all national courts, regardless of their rank in the national judicial system. Any provision of a national legal system or any legislative, administrative, or judicial practice that impairs the effectiveness of EU law by withholding from the national court having jurisdiction to apply such law the power to do everything necessary at the moment of its application to set aside national legislative provisions which might prevent EU rules from having full force and effect are incompatible with the requirements which arise from the very nature of EU law.
- Allowing national laws to obstruct the application of EU law would undermine the uniformity and effectiveness of the EU legal order.

## Legal Principles

- **Supremacy of EU Law:** EU law takes precedence over any conflicting provision of national law, whether prior or subsequent to the EU law. This principle, affirmed in _Costa v ENEL_, means that Member States have definitively transferred sovereign rights to the EU in certain fields, creating an autonomous legal order.
- **Direct Effect of EU Law:** Directly applicable provisions of EU law confer rights on individuals which national courts must protect. National courts are obliged to apply EU law and to protect the rights so conferred.
- **Obligation of National Courts to Disapply Conflicting National Law:** National courts are under a duty to apply EU law in its entirety and to set aside any provision of national law which may conflict with it, whether that national law was adopted before or after the EU rule. This is a fundamental requirement of EU law and does not require or depend on any prior act of a national institution.
- **Uniformity and Effectiveness of EU Law:** The consistent and uniform application of EU law in all Member States is essential for the functioning of the EU. National courts play a role in ensuring this uniformity and effectiveness by giving precedence to EU law.
- **Judicial Enforcement by National Courts:** National courts are primary enforcers of EU law within their respective jurisdictions. They must ensure that EU law is fully effective.

## Conclusion

The _Simmenthal II_ judgment is a foundational decision in EU law, significantly clarifying the practical implications of the supremacy and direct effect of EU law within the national legal systems of Member States. The ECJ's definitive statement that national courts must independently disapply conflicting national provisions, without needing to wait for legislative or higher court action, reinforced the operational primacy of EU law. This principle is essential for ensuring the consistent and uniform application of EU law across all Member States, thereby contributing to the effectiveness and integrity of the EU legal order.

Simmenthal II (Case C-106/77) [1978] ECR 629