The Court of Justice held that certain EEC Treaty provisions can confer rights on individuals enforceable in national courts, articulating the Community as a "new legal order" and laying the foundation for direct effect.
The Court stated that Community law cannot be overridden by domestic legal provisions, grounding the principle of supremacy/primacy as necessary for uniform effectiveness of EU obligations.
The Court reaffirmed primacy while holding that review of Community measures must occur within Community law, and linked the protection of fundamental rights to general principles of Community law.
The Court accepted that, under conditions, provisions of a directive may be relied upon by individuals against the state, helping establish vertical direct effect of directives in EU law.
The Court stated that, absent EU procedural rules, enforcement is governed by national law, but subject to the requirements of equivalence and effectiveness, shaping how directly effective rights are vindicated domestically.
The Court held that a national court must give full effect to directly applicable EU law by setting aside conflicting national provisions (even if adopted later), without awaiting prior repeal or constitutional review.
The Court held that once a directive’s implementation deadline has passed, a Member State may not rely on its failure to transpose to the detriment of individuals—supporting vertical direct effect and an “estoppel”-type reasoning against the state.
The Court confirmed that where a directive provision is sufficiently clear, precise, and unconditional—and the deadline has passed—individuals may invoke it against the state, sharpening the doctrinal test for directive direct effect.
Building on primacy, the Court required that national courts be able to grant interim relief (including disapplying national rules that prevent it) to ensure the full effectiveness of directly effective EU law.
The Court held that Member States may be liable in damages to individuals for failure to implement EU directives, strengthening the effectiveness of EU law where direct effect cannot fully secure rights.
The Court developed a general doctrine of Member State liability for breaches of EU law (beyond non-implementation), specifying core conditions for damages claims and reinforcing EU law’s practical effectiveness.
The Court held that failure to transpose a directive within the prescribed period can itself amount to a sufficiently serious breach triggering state liability, consolidating the Francovich/Brasserie line.
Key CJEU rulings on supremacy and direct effect (1963–1996)
