Supremacy of European Union Law

The supremacy of European Union law is a fundamental principle of EU law that establishes the hierarchy of legal norms within the legal system of the European Union. It essentially means that EU law takes precedence over national laws of EU member states in cases of conflict or inconsistency.

Treaty basis: The principle of supremacy is derived from the EU treaties, which are the founding legal documents of the EU. The treaties explicitly state that EU law has primacy over national laws. This principle was first established by the Court of Justice of the European Union (CJEU) in the landmark case of Costa v ENEL in 1964.

Primacy and direct effect: The principle of supremacy ensures that EU law prevails over conflicting national laws. It means that if there is a conflict between EU law and the laws of a member state, EU law takes precedence and must be applied and enforced by national courts. In addition to primacy, certain EU laws also have direct effect, meaning that individuals can directly invoke them before national courts.

Harmonisation and uniform application: The supremacy of EU law is essential for ensuring the harmonisation and uniform application of laws across the EU. It prevents fragmentation and inconsistencies in the interpretation and application of EU law by national authorities, promoting legal certainty and the functioning of the internal market.

National court obligation: National courts have an obligation to ensure the application of EU law and to set aside any conflicting national laws. They are required to interpret and apply national laws in line with EU law and to refer questions of EU law to the CJEU for preliminary rulings if necessary. National courts act as guardians of EU law within their respective jurisdictions.

Limits and principles of proportionality: While EU law has supremacy over national laws, it must still respect the principles of proportionality and subsidiarity. EU legislation should only be adopted when it is necessary and when the objectives cannot be sufficiently achieved by member states individually. This ensures a balance between the EU's central authority and the autonomy of member states.

Loyalty and cooperation: Member states have a duty of loyalty and cooperation towards the EU. They are expected to comply with EU law, implement EU directives, and ensure effective enforcement of EU rules within their territories. Member states are also required to cooperate with the EU institutions and each other to achieve the objectives of the EU.

The principle of the supremacy of EU law is a foundational element of the EU's legal framework. It ensures the effectiveness and uniformity of EU law across member states, promotes legal certainty, and contributes to the development and functioning of the EU as a single legal order.
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