Costa v ENEL [1964]

Case 6/64 Flaminio Costa v ENEL [1964] stands as a landmark decision in the history of the European Court of Justice, establishing the primacy of European Union law (then Community law) over the laws of its member states.

Flaminio Costa, a Milanese lawyer and shareholder of Edisonvolta, opposed the nationalisation of the electricity sector in Italy. When he received an electricity bill from ENEL, the company established by the nationalisation law, he refused to pay, arguing that the nationalisation law violated both the Italian Constitution and the EEC Treaty.

Costa brought the matter before the Justice of Peace of Milan, requesting a referral to both the Italian Constitutional Court and the European Court of Justice. The Italian Constitutional Court ruled that, while the Italian Parliament could pass laws limiting sovereignty to join international organisations like the EEC, such laws did not hold a special rank in the legal hierarchy. The Treaty of Rome, incorporated into Italian law in 1957, was deemed subordinate to the electricity nationalisation law enacted in 1962.

In a subsequent challenge, Costa's case was referred to the European Court of Justice by Justice of Peace Vittorio Emanuele Fabbri, raising questions about the nationalisation law's consistency with the EEC Treaty on various grounds. The Italian government contended that the reference was inadmissible, as the nationalisation statute should prevail even if conflicting with the EEC Treaty.

The European Court of Justice dismissed the inadmissibility plea and emphasised the unique nature of the EEC Treaty, creating its own legal order binding upon member states. The ECJ asserted that community law could not be overridden by domestic legal provisions without undermining its character as community law. The judgment established the principle that EU law is supreme and cannot be displaced by domestic laws.

On the merits, the ECJ held that certain provisions of the EEC Treaty had no direct effect and could not be invoked by individuals against national laws. The court interpreted the right of establishment narrowly and left it to the referring court to determine the consistency of the nationalisation law with the EEC Treaty on commercial monopolies.

The significance of the Costa v ENEL case lies in its establishment of the principle of supremacy in EU law. Although Article I-6 of the proposed European Constitution emphasised this primacy, the constitution was never ratified. The subsequent Treaty of Lisbon (2007) did not include an article on primacy but included a Declaration recalling the Costa v ENEL judgment. French Judge Robert Lecourt later reflected that these decisions merely gave effect to the treaties' commands, reinforcing the supremacy of EU law.
Back to blog
UOL Case Bank

UOL Case Bank

Upon joining, you become a valuable UOL student and gain instant access to over 2,100 case summaries. UOL Case Bank is constantly expanding. Speed up your revision with us now.

Subscribe Now

Where are our students from?

Yale University
Council of Europe
Baker Mckenzie 
University of Chicago
Columbia University
New York University
University of Michigan 
INSEAD
University College London (UCL)
London School of Economics (LSE)
King’s College London (KCL)
University of London
University of Manchester
University of Zurich
University of York
Brandeis University
University of Exeter
University of Sheffield
Boston University
University of Washington
University of Leeds
University of Law
Royal Holloway, University of London 
Birkbeck, University of London
SOAS, University of London
University of Kent
University of Hull
Queen’s University Belfast
Toronto Metropolitan University
Hong Kong University of Science and Technology
University of Buckingham

  • Criminal Practice

    Diagrams and Charts

    Our carefully designed diagrams and charts will guide you through complex legal issues.

  • Criminal Law

    Clear and Succinct Definitions

    Key concepts are concisely defined to help you understand legal topics quickly.

  • Property Law

    Statutory Provisions

    Statutory provisions are provided side by side with legal concepts to help you swiftly locate the relevant legislation.

  • Public Law

    Case Summaries

    We have summarised important cases for you so that you don't need to read long and boring cases.

  • Evidence

    Rules and Exceptions

    Rules and exceptions are clearly listed so that you know when a rule applies and when it doesn't.

  • Company Law

    Terminology

    Legal terms and key concepts are explained at the beginning of each chapter to help you learn efficiently.

  • Case Law

    Case law is provided side by side with legal concepts so that you know how legal principles and precedents were established.

  • Law Exam Guide

    Law Essay Guide

    You will learn essential law exam skills and essay writing techniques that are not taught in class.

  • Law Exam Guide

    Problem Question Guide

    We will show you how to answer problem questions step by step to achieve first-class results.

  • Conflict of Laws

    Structured Explanations

    Complex legal concepts are broken down into concise and digestible bullet point explanations.

  • Legal System and Method

    Legal Research

    You will learn legal research techniques with our study guide and become a proficient legal researcher.

  • Jurisprudence and Legal Theory

    Exam-focused

    All essential concepts, principles, and case law are included so that you can answer exam questions quickly.