The Development of European Union Law from the Schuman Plan to the Treaty of Lisbon

The Beginnings of European Supranationalism

Lingering distrust of Germany in the wake of the Second World War led French Foreign Minister Robert Schuman to propose that coal and steel (commodities essential for conducting conventional wars) be placed under the control of a supranational entity. The 1950 ‘Schuman Plan’ proposed the establishment of a common market for these commodities, with participating countries transferring necessary power to an independent authority.1 The Schuman Plan led to the formation of the European Coal and Steel Community (‘ECSC’) by treaty in 1951.2 The ECSC consisted of four primary institutions: a legislative and executive body called the High Authority;3 the Special Council of Ministers, which represented the interests of the member states and harmonised High Authority actions with domestic policies,4 and gave assent to important decisions;5 a supervisory and advisory Common Assembly consisting of legislators from member states;6 and the Court of Justice, which ensured that the rule of law was applied in the interpretation and application of the ECSC Treaty and related regulations.7

In 1955 the foreign ministers of the ECSC members resolved to ‘pursue the establishment of a United Europe through the development of common institutions, a progressive fusion of national economies, the creation of a common market and harmonisation of social policies’.8 The result was two treaties, both signed in 1957, establishing the European Economic Community (‘EEC’)9 and the European Atomic Energy Community (‘Euratom’).10 The EEC quickly became the most important of the three communities and was at the centre of European integration that led to the eventual founding of the European Union (‘EU’).11 Alongside the EEC and Euratom treaties, the 1956 Common Institutions Convention established a single assembly (the European Parliament) and a single European Court of Justice (‘ECJ’) for all three communities.12 The 1965 Merger Treaty furthered integration by providing that the Commission of the EEC would replace both the Euratom Commission and the ECSC High Authority, and that the Council of the EEC would take over the functions of the Euratom and ECSC Councils.13 Consequently, the four primary institutions of the European Communities emerged as the European Commission, the Council of Ministers, the European Parliament, and the European Court of Justice.

Development of Constitutional Principles

In the decade following the establishment of the EEC, certain ‘constitutional principles’ were developed through ECJ case law that are fundamental to the functioning of the current EU legal system, and which have guided the development of EU law: supremacy, direct effect, and direct applicability.14 Because member states were unable to ‘react with unanimity’ to these developments, the ‘legal system began to evolve along paths that could not be predicted from the constellation of the Member State preferences at any given time.’15

The principle of supremacy derives from the legal system created by the EU’s constitutive treaties.16 Under this principle, ‘EU law prevails over all national laws [including constitutional laws] within the scope of EU law.17 National laws yield to constitutive treaties and legislative acts of the EU,18 general principles of EU law,19 and international agreements concluded by the EU.20 Conflicts between EU law and national law are resolved in favour of the former, and national courts must set aside national legislation where conflicts arise. Kaczorowska explains:

It is correct to say that in order to achieve the objectives of the founding Treaties, to uniformly apply EU law throughout the EU, to ensure the proper functioning of the internal market, and for the EU to become a fully integrated structure, the supremacy of EU law must be respected by the Member States. Otherwise, the EU will cease to exist as we currently understand it.21

Under the principle of direct effect, certain laws of the EU confer rights upon individuals that national courts are required to protect.22 The ECJ has consistently maintained that a provision of EU law will have direct effect where it confers rights on individuals that can be invoked in domestic proceedings.23 ‘Vertical direct effect’ enables individuals to rely on EU law in proceedings against member states. Constitutive treaties, the Charter of Fundamental Rights, general principles of EU law, regulations, directives, decisions and international agreements are all able to have vertical direct effect.24 ‘Horizontal direct effect’ enables individuals to rely on EU law when bringing proceedings against other individuals. Regulations are able to have horizontal effect,25 but the situation is less clear with regard to the Charter of Fundamental Rights and general principles of EU law.26 Directives will almost never have direct horizontal effect,27 though decisions will if addressed to individuals rather than member states.28 It is unclear whether international agreements can have horizontal effect.29

The principle of direct applicability stems from the peculiar nature of EU law as a legal system of its own.30 Regulations are directly applicable in all member states31 and the rules of EU law must be uniformly applied.32 As a result of being directly applicable, regulations do not need to be implemented into domestic law to take effect,33 and this is in fact discouraged by the ECJ.34

Renewed Enthusiasm for European Integration

Disputes over the competences of the European Commission and the method of voting within the Council of Ministers led to a period of stagnation from the late 1960s to the early 1980s.35 However, in 1985 the European Council (a regular meeting of heads of government of the member states separate from the Council of Ministers) adopted the Dodge Report, which introduced a co-decision procedure that gave more power to the European Parliament, recognised European Council as a Community institution, and led to the preparation of a new Treaty on European Union.36 Lord Cockfield’s white paper, adopted in July 1985, proposed the establishment of an internal market by the end of 1992, identified remaining barriers to trade, proposed 300 legislative measures to eliminate those barriers, and set out a timetable for the elimination process.37 An intergovernmental conference to revise the EEC Treaty was also convened in 1985, the key outcome of which was the Single European Act,38 which set a firm date for the completion of the internal market (31 December 1992),39 and nearly 300 legislative measures were adopted in order to meet this goal. Additionally, new competences were conferred upon the EEC concerning economic and social cohesion, research and technological development, and the environment.40

The Founding of the European Union

The European Council summit of 9–10 December 1991 approved the Treaty on European Union (‘TEU’), intended to be ratified by the end of 1992.41 The EU was initially based on a ‘temple’ structure consisting of: common provisions laying down general objectives (the ‘roof’); the EEC (renamed ‘the European Community’), the Common Foreign and Security Policy, and Justice and Home Affairs (the three ‘pillars’); and final provisions not covered elsewhere (the ‘plinth’). Danish voters initially rejected the TEU, but after reassurance from the European Council Denmark approved it by referendum in May 1993.42 Despite challenges in the Constitutional Court of Germany43 and the High Court of England and Wales,43 these were unsuccessful and the TEU entered into force on 1 December 1993.

The TEU was initially criticised for undermining the unity and cohesiveness of the EU’s legal order, for excluding the ECJ and European Parliament from several areas, and for being both lengthy and poorly drafted.44 Despite these flaws, it introduced many fundamental changes, including the introduction of EU citizenship and reinforcement of the powers of the European Parliament.45 Under the TEU, the EEC Treaty was renamed the ‘Treaty Establishing the European Community’ and was heavily amended to restrict European Community involvement in national matters while redefining the objectives of the community in areas such as health, education and consumer protection, and extended its competences in environmental protection and developmental aid.46 The European Commission was made more accountable to the European Parliament, and the latter’s involvement in decision-making was enlarged.47 The Common Foreign and Security Policy pillar had self-evident aims, but was also intended to lead to a common defence policy if possible.48 The Justice and Home Affairs pillar covered intergovernmental cooperation in matters of criminal and civil justice, asylum, immigration and visas, matters which were gradually transferred to the European Community.49

The original TEU was subsequently amended in 1999 by the Treaty of Amsterdam, which extended the objectives of the European Union and imposed obligations that legislative measures be assessed against the values of eliminating gender discrimination and protecting the environment.50 Further amendments by the Treaty of Nice in 2003 resolved several of the shortcomings of the Treaty of Amsterdam.51

The Treaty of Lisbon

An attempt to implement a Constitution of the European Union was made in the mid-2000s, following the adoption of the Declaration on the Future of the European Union by the European Council summit at Laeken in 2001.52 The Laeken Declaration posed a number of questions to be debated and considered by a convention focusing on better division and definition of competences, simplification of instruments, resolution of democratic deficits, and improvement of democratic processes, transparency and effectiveness. The European Constitution was signed in October 2004, but the November 2006 deadline for entry into force was not met because referenda for ratification failed in France and the Netherlands. Although 18 member states had ratified the Constitution it was abandoned in June 2007 and a further intergovernmental conference was arranged to consider alternative approaches to achieving the Constitution’s aims.53

The failed European Constitution was superseded by the Treaty of Lisbon, which entered into force in 2009.54 With the exception of Ireland, which was constitutionally-bound to hold a referendum, all member states ratified the treaty through ordinary legislative processes. A challenge was launched in the Constitutional Court of Germany, which ruled in 2009 that the Treaty of Lisbon did not transform the EU into a federal state, that EU citizenship did not replace national citizenship, and that member states were not required to provide troops for a ‘European Army.’55 On the other hand, the Court determined that modifications to domestic legislation were required to ensure greater participation of the German legislature in controlling and supervising EU affairs. Importantly, the Court confirmed that the supremacy of EU law derives from German legislation conferring law-making power on the EU, and not from the EU itself.

Articles 1 and 2 of the Treaty of Lisbon make amendments to the TEU and the EC Treaty (which was renamed the Treaty on the Functioning of the European Union (‘TFEU’)); article 3 states that the Treaty of Lisbon is concluded for an indefinite period; article 4 concerns the attached protocols 1 and 2; article 5 deals with renumbering provisions; article 6 concerns the ratification procedure; and article 7 confirms the authenticity of each official language and designates Italy as the repository of the Treaty. Attached are two protocols, one annex, and the final act of the intergovernmental conference. The TEU and TFEU now include 37 protocols, two annexes, and 65 declarations. Protocol 1 of the Treaty of Lisbon amends protocols attached to the TEU, the former EC Treaty and Euratom Treaty, and Protocol 2 amends only the latter treaty. The Treaty of Lisbon is a ‘wrapper’ treaty that effects amendments to other treaties.

Elements of the European Constitution are present, but the Treaty of Lisbon did not merge the three existing treaties into one. Article 1(3) of the TEU states that the EU is based on two treaties, being the TEU and TFEU. Both treaties are of equal legal value. The TFEU abolished the pillar structure, but provides special procedures for the Common Foreign and Security policy. The Treaty of Lisbon also abolished the distinction between the European Community and the European Union, with the latter replacing and succeeding the former. The EU has international legal personality, as is the only supranational entity able to enter into agreements. Euratom remains outside the EU.

The European Union Today

The TEU states that the EU is founded on the values of: respect for human dignity, freedom, democracy, equality and the rule of law; respect for human rights; and pluralism, tolerance, justice, solidarity and gender equality.56 The overarching and specific objectives of the EU are to pursue peace, freedom, security, sustainable development, social justice, non-discrimination, equality, cultural and linguistic diversity, eradication of poverty, and protection of human rights. While the Treaty of Lisbon did not revive the failed European Constitution, it did adopt some of the aspects and necessary reforms that were intended, while avoiding terminology that would suggest state-like status, such as anything indicating a federal ambition, or the concepts of a constitution, anthem, motto or flag. The Treaty of Lisbon effected the reforms necessary for the ever-enlarging EU by introducing improvements in efficiency of the decision-making processes and allowing for greater democratisation of the EU. Specific improvements included giving more legislative, budgetary and political powers to the European Parliament, the involvement of national legislatures, more rights for citizens (and the ability to enforce those rights), and clarification of the division of competences between the EU and its member states.

European Union Law in Action — the Data Retention Directive

In 2006 the EU issued a directive (the ‘Data Retention Directive’) requiring member states to store telecommunications data for a period of 6–24 months.57 The Data Retention Directive provides a helpful case study for the legislative and judicial processes of the EU. Under the EC Treaty (now the TFEU), the European Parliament and the Council of the European Union may adopt regulations, directives, decisions, recommendations and opinions.58 Unlike regulations, directives specify a result to be achieved and leave member states to determine the form and method of implementation at the national level, a processed called ‘transposition.’ Transposition is a double-edged sword. By being less specific than regulations and not having direct application, directives provide EU-wide minimum standards while giving member states flexibility in implementation. This allows directives to be transposed in accordance with national constitutions and member states’ public policy considerations. On the other hand, it can lead to significant variance and inconsistency in transposition between member states, as well as lengthy delays in implementation.

Under the Data Retention Directive, member states implemented varying periods of storage of retained data, with some even specifying different periods for different types of data.59 The purposes for which retained data could be used varied from serious crimes to all criminal offences, and most member states allowed access for purposes beyond those covered by the Directive.60 Additionally, there was significant variation concerning which authorities could access the retained data and under which procedures and conditions.61

The European Commission successfully brought proceedings against Austria for its delay in transposing the Directive;62 Austria had delayed due to concerns relating to the protection of privacy. The constitutional courts of Romania,63 Germany,64 and the Czech Republic65 all declared the transposing laws to be in breach of constitutional and international protections of privacy, while in Bulgaria66 and Cyprus67 some aspects of the transposing laws were declared unconstitutional and required revising. On 8 April 2014 the ECJ delivered its judgment on the validity of the Data Retention Directive, stating that ‘the EU legislature has exceeded the limits imposed by compliance with the principle of proportionality in the light of Articles 7, 8 and 62(1) of the Charter [of Fundamental Rights of the European Union and therefore] Directive 2006/24/EC … is invalid.’68

The Directive has therefore ceased to have effect, but member states have reacted differently. Although constitutional courts in some member states held the transposing laws to be invalid, some member states have kept or modified their implementations in an attempt to conform with the ECJ’s decision, and other member states have refrained from introducing data retention regimes. The United Kingdom quickly enacted new legislation intended to replace the regulations that had implemented the Data Retention Directive.69 Judicial review proceedings were swiftly initiated,70 alleging that the new legislation was incompatible with the European Convention on Human Rights71 (a non-EU treaty) and the Charter of Fundamental Rights of the European Union.72 These proceedings were generally successful, the High Court of England Wales holding that the legislation was incompatible with the laws of the EU, but allowing room and time for the British Parliament to enact replacement legislation that is ‘compliant with EU law.’73


For more than half a century, EU law has been developing into a unique supranational legal system that incorporates elements of international law, traditional parliamentary democracy, and case law developed by the ECJ. Through its international legal personality and internal market, the EU is able to negotiate on behalf of an expanding bloc of European countries. Legislative measures provide for consistency and enforcement of minimum standards across the EU, evidenced especially by the strong emphasis on the protection of human rights. This provides guarantees for individuals and businesses within the EU, but also for those trading with and importing into EU member states. EU law is both robust and flexible, providing for a high degree of uniformity across its member states without trampling upon their sovereignty.

  1. Alina Kaczorowska, European Union Law (Routledge, 3rd ed, 2013) 5–6. 

  2. Treaty Instituting the European Coal and Steel Community, signed 18 April 1951, 261 UNTS 140 (entered into force 23 July 1952). 

  3. Ibid arts 8–19. 

  4. Ibid art 26. 

  5. Ibid art 28. 

  6. Ibid arts 20–25. 

  7. Ibid arts 31–34. 

  8. D Lasok, Law and Institutions of the European Union (Butterworths, 6th ed, 1994). 

  9. Treaty Establishing the European Economic Community, opened for signature 25 March 1957, 298 UNTS 11 (entered into force 1 January 1958). 

  10. Treaty Establishing the European Atomic Energy Community, opened for signature 25 March 1957, 298 UNTS 167 (entered into force 1 January 1958). 

  11. Kaczorowska, above n 1, 9. 

  12. Convention Relating to Certain Institutions Common to the European Communities, signed 25 March 1957, 298 UNTS 5 (entered into force 1 January 1958). 

  13. Treaty Establishing a Single Council and a Single Commission of the European Communities, signed 8 April 1965, 1348 UNTS 81 (entered into force 1 July 1967). 

  14. Costa v ENEL (C-6/64) [1964] ECR 585; NV Algemene Transport-en Expeditie Onderneming van Gend & Loos v Netherlands Inland Revenue Administration (C-26/62) [1963] ECR 1; Amministrazione delle Finanze dello Stato v Simmenthal SpA (C-106/77) [1978] ECR 629. 

  15. Alec Stone Sweet, ‘The European Court of Justice’ in Paul Craig and Gráinne de Búrca (eds), The Evolution of EU Law (Oxford University Press, 2nd ed, 2011). 

  16. Costa v ENEL (C-6/64) [1964] ECR 585. 

  17. Kaczorowska, above n 1, 240. 

  18. Politi SAS v Ministry for Finance of the Italian Republic (C-43/71) [1971] ECR 1039; SpA Marimex v Ministero delle Finanze (C-84/71) [1972] ECR 89; Rewe-Handelsgesellschaft Nord mbH v Hauptzollamt Kiel (C-158/80) [1981] ECR 1805; Becker v Finanzamt Münster-Innenstadt (C-8/81) [1982] ECR 53; Salumificio de Cornuda v Amministrazione delle Finanze dello Stato (C-130/78) [1979] ECR 867. 

  19. Wachauf v Bundesamt für Ernährung und Forstwirtschaft (C-5/88) [1989] ECR 2609. 

  20. Douaneagent der NV Nederlandse Spoorwegen v Inspecteur der Invoerrechten en Accijnzen (C-38/75) [1975] ECR 1439; Amministrazione delle Finanze dello Stato v SPI (C-267–269/81) [1983] ECR 801. 

  21. Kaczorowska, above n 1, 242. 

  22. NV Algemene Transport-en Expeditie Onderneming van Gend & Loos v Netherlands Inland Revenue Administration (C-26/62) [1963] ECR 1. 

  23. Kaczorowska, above n 1, 263. 

  24. NV Algemene Transport-en Expeditie Onderneming van Gend & Loos v Netherlands Inland Revenue Administration (C-26/62) [1963] ECR 1; Lütticke v Hauptzollampt Saarlous (C-57/65) [1966] ECR 205; Charter of Fundamental Rights of the European Union [2012] OJ C 326/391 art 51(1); Valero v Fondo de Garantía Sararial (Fogasa) (C-520/03) [2004] ECR I-12065; Caballero v Fondo de Garantía Sararial (Fogasa) (C-442/00) [2002] ECR I-11915; Emeka NE v Ipourgos Ikonomikon (C-183/04) [2006] ECR I-8167; Leonesio v Italian Ministry of Agriculture (C-93/71) [1972] ECR 287; Kaczorowska, above n 1, 297–8. 

  25. Defrenne v Sabena (C-43/75) [1976] ECR 455; Antonio Munñoz Cia SA v Frumar Ltd (C-253/00) [2002] ECR I-7289. 

  26. Kaczorowska, above n 1, 273–7. 

  27. Marshall v Southampton and South West Hampshire Area Health Authority (C-152/84) [1986] ECR 723. 

  28. Kaczorowska, above n 1, 297–8. 

  29. Ibid 299. 

  30. Ibid 304, citing Costa v ENEL (C-6/64) [1964] ECR 585. 

  31. Treaty on the Functioning of the European Union, opened for signature 7 February 1992, [2009] OJ C 115/199 (entered into force 1 November 1993) art 288. 

  32. Amminstrazione delle Finanze dello Stato v Simmenthal SpA (C-106/77) [1978] ECR 629. 

  33. Treaty on the Functioning of the European Union, opened for signature 7 February 1992, [2009] OJ C 115/199 (entered into force 1 November 1993). 

  34. Fratelli Variola SpA v Amminizstrazione Italiana delle Finanze (C-34/73) [1973] ECR 981. 

  35. Kaczorowska, above n 1, 10. 

  36. Ibid 14. 

  37. Ibid. 

  38. Single European Act, signed 17/28 February 1986, 1754 UNTS 111 (entered into force 1 July 1987). 

  39. Ibid art 13. 

  40. Ibid arts 21–25. 

  41. Treaty on European Union, opened for signature 7 February 1992, [1992] OJ C 191/1 (entered into force 1 November 1993). 

  42. Ibid 19. 

  43. Matthias J Herdegen, ‘Maastricht and the German Constitutional Court: Constitutional Restraints for an “Ever Closer Union”’ (1994) 31 Common Market Law Review 235.  2

  44. Kaczorowska, above n 1, 22. 

  45. Ibid. 

  46. Ibid 20. 

  47. Ibid. 

  48. Ibid 19. 

  49. Ibid 20. 

  50. Treaty of Amsterdam Amending the Treaty on European Union, the Treaties Establishing the European Communities and Certain Related Acts, opened for signature 2 October 1997, [1997] OJ C 340/1 (entered into force 1 May 1999). 

  51. Treaty of Nice Amending the Treaty on European, the Treaties Establishing the European Communities and Certain Related Acts, opened for signature 26 February 2001, [2001] OJ C 80/1 (entered into force 1 February 2003). 

  52. Kaczorowska, above n 1, 24. 

  53. Ibid 25. 

  54. Treaty of Lisbon Amending the Treaty on European Union and the Treaty Establishing the European Community, opened for signature 26 February 13 December 2007, [2007] OJ C 306/1 (entered into force 1 December 2009). 

  55. Bundesverfassungsgericht [Constitutional Court of Germany], 2 BvE 2/08, 30 June 2009. 

  56. Treaty on European Union, opened for signature 7 February 1992, [2009] OJ C 115/13 (entered into force 1 November 1993) art 2. 

  57. Directive 2006/24/EC of the European Parliament and of the Council of 15 March 2006 on the Retention of Data Generated or Processed in Connection with the Provision of Publicly Available Electronic Communications Services or of Public Communications Networks and Amending Directive 2002/58/EC [2006] OJ L 105/54. 

  58. Treaty Establishing the European Community, opened for signature 7 February 1992, [1992] OJ C 224/6 (entered into force 1 November 1993), as amended by Treaty of Nice Amending the Treaty on European Union, the Treaties Establishing the European Communities and Certain Related Acts, opened for signature 26 February 2001, [2001] OJ C 80/1 (entered into force 1 February 2003) art 249; Treaty on the Functioning of the European Union, opened for signature 7 February 1992, [2002] OJ C 115/199 (entered into force 1 November 1993) art 288. 

  59. European Commission, ‘Evaluation Report on the Data Retention Directive (Directive 2006/24/EC)’ (Report from the Commission to the Council and the European Parliament, 2011) 13–14. 

  60. Ibid 6–8. 

  61. Ibid 9–12. 

  62. European Commission v Austria (Court of Justice of the European Union, C 1-189/09, 29 July 2010). 

  63. Curtea Constituţională a României [Constitutional Court of Romania], No 1258, 8 October 2009 reported in 789 Official Monitor, 23 November 2009. 

  64. Bundesverfassungsgericht [Federal Constitutional Court of Germany], 1 BvR 256/08, 2 March 2010. 

  65. Ústavní soud České republiky [Constitutional Court of the Czech Republic], Judgment of the Constitutional Court of 22 March on the provisions of section 97 paragraph 3 and 4 of Act No 127/2005 Coll on electronic communications and amending certain related acts as amended, and Decree No 485/2005 Coll on the data retention and transmission to competent authorities, 22 March 2011 reported in Official Gazette, 1 April 2011. 

  66. Bulgarian Supreme Administrative Court, No 13627, 11 December 2008. 

  67. Supreme Court of Cyprus, Appeal Cases 65/2009, 78/2009, 82/2009 and 15/2010–22/2010, 1 February 2011. 

  68. Digital Rights Ireland Ltd v Minister for Communications, Marine and Natural Resources (Court of Justice of the European Union, C-293/12 & C-594/12, 8 April 2014). 

  69. Data Retention and Investigatory Powers Act 2014 (UK) c 27. 

  70. R (Davis) v Secretary of State for the Home Department [2015] EWHC 2092 (Admin). 

  71. Convention for the Protection of Human Rights and Fundamental Freedoms, opened for signature 4 November 1950, 213 UNTS 221 (entered into force 3 September 1953). 

  72. Charter of Fundamental Rights of the European Union [2012] OJ C 326/391. 

  73. R (Davis) v Secretary of State for the Home Department [2015] EWHC 2092 (Admin).