1. Treaty of Maastricht
The Treaty on European Union ( OJ C191), abbreviated to the ‘EU Treaty’, was signed in Maastricht on 7 February 1992. The contracting parties when the treaty was signed were the 12 Member States that made up the three European Communities at the time (European Community) (Belgium, Denmark, France, Germany, Greece, Ireland, Italy, Luxembourg, the Netherlands, Portugal, Spain and the United Kingdom). The EU Treaty describes itself as marking a new stage in the process of creating an ever closer union among the peoples of Europe and emphasizes in its preamble the historic importance of the ending of the division of the European continent and the need to create firm bases for the construction of the future Europe.
The Danish people rejected the treaty in their first referendum and did not agree to it until a second referendum was held, after the European Council (Council and the European Council) had agreed on certain special rules for Denmark in December 1992. In Germany, the EU Treaty was the subject of several constitutional complaints; some of these were found to be inadmissible whilst others were dismissed as unfounded (BVerfG 12 October 1993, BVerfGE 89, 155). It finally became possible for the EU Treaty to enter into force on 1 November 1993.
The Union created by this treaty is founded on the European Communities, together with the Common Foreign and Security Policy (CFSP) and cooperation in the fields of justice and home affairs. Hence, there is talk of a three-pillar structure. In the second and third pillars the decision-making procedure is based on intergovernmental cooperation (in contrast to the Community method characteristic of the European Communities).
The EU Treaty is designed as a framework treaty. Part I contains provisions that are common to all of the following parts. They deal, in particular, with the aims of the Union, its structure, consistency of Union action and the European Council (Council and the European Council) as a political steering body. Further topics include respect for the national identity of the Member States, the democratic imperative and the Union’s commitment to fundamental rights. Titles II–IV contain provisions amending the treaties on the three European Communities. Titles V and VI are dedicated to the CFSP and cooperation in the fields of justice and home affairs. Title VI (Final Provisions) contains, inter alia, the rule on limited competency afforded to the Court of Justice of the European Communities (European Court of Justice (ECJ)) with regard to provisions that do not relate to the amendment of earlier treaties. Most of the EU Treaty is made up of extensive provisions amending the Treaty establishing the European Economic Community. The name ‘European Economic Community’ was changed to ‘European Community’ and the Treaty establishing the European Economic Community was changed to the Treaty establishing the European Community (EC Treaty).
One key reform was the introduction of provisions creating an economic and monetary union in the EC Treaty (European Economic Constitution). Another important innovation was the introduction of Union citizenship common to the nationals of the Member States to which specific rights are attached, such as a right of residency throughout the Union and the right to stand for election and vote in the state of residence in municipal and European elections. Community competency was expanded to include a number of new political areas, eg consumer protection (consumers and consumer protection law). At the same time, the EU Treaty elevated the principle of subsidiarity, which until then had only been provided for in the environmental protection field, to the status of a general principle. It strengthened the European Parliament, in particular by introducing the co-decision procedure and participation in the investiture of the European Commission, and considerably expanded the number of instances in which the Council can make decisions by a qualified majority. Innovations of an institutional kind included the establishment of a Committee of the Regions with an advisory function and the appointment of an ombudsman by the European Parliament.
With its CFSP the Union pursued its aim of asserting its identity on the international scene. The EU Treaty named as a longer-term perspective the introduction of a common defence policy. A number of specific objectives were laid down in the CFSP in relation to joint action. It is intended to preserve peace, strengthen international security and develop and consolidate democracy and the rule of law as well as respect for human rights and fundamental freedoms.
A number of matters were designated as being of common interest in the title on cooperation on justice and home affairs; amongst others asylum policy, immigration policy, judicial cooperation in civil and criminal matters, as well as police collaboration in combating drugs and terrorism in connection with the organization of a Union-wide system for the exchange of information within a European Police Office (Europol).
There are 17 protocols annexed to the treaty. These protocols contain, for example, the Statute of the European System of Central Banks and of the European Central Bank and the Statute of the European Monetary Institute. There are also protocols on the excessive deficit procedure and the convergence criteria which shall guide the Union in taking decisions on the passage to the third stage of economic and monetary union. Danish reservations were taken into account, inter alia, by the Protocol on the acquisition of property in Denmark. The Protocol concerning Art 119 of the Treaty establishing the European Community is a response to the judgment of the European Court of Justice in Barber (ECJ Case C‑262/88 – Barber  ECR I‑1889).
New ways of further developing the social dimension of the Union despite British opposition were pursued. The Member States of the European Union, except for the United Kingdom, signed an agreement on social policy. It was annexed to a protocol on social policy in which the contracting states to the agreement were authorized to have recourse to the institutions, procedures and mechanisms of the EC Treaty for the purposes of taking amongst themselves and applying as far as they were concerned the acts and decisions required for giving effect to the said agreement.
Since the amendment of the EEC Treaty was a central element of the EU Treaty, the amendments to the EU Treaty will be set out below in conjunction with the simultaneous amendments to the EC Treaty.
2. Treaty of Amsterdam
The European Union made its first progression in the Treaty of Amsterdam, amending the Treaty on European Union, the Treaties establishing the European Communities and certain related acts, which was signed in Amsterdam on 2 October 1997 ( OJ C340). It entered into force on 1 May 1999 after the Member States of the European Union, whose number had by then increased to 15 as a result of the accession of Austria, Finland and Sweden, had ratified it in accordance with their individual constitutional laws. The treaty was heavily influenced by the looming eastern enlargement of the European Union. Its overall concept is a people’s Europe.
Like the Maastricht Treaty, the Treaty of Amsterdam is a framework treaty. It consists of three parts, an annex and 13 protocols. The first part, which is headed ‘Substantive amendments’, contains amendments to the EU Treaty and the Treaties establishing the European Communities. In Part Two the Treaties establishing the European Communities, including their annexes and protocols, are amended under the heading ‘Simplification’ for the purpose of deleting lapsed provisions and adapting certain of its provisions accordingly. Part Three, which contains general and final provisions, includes, inter alia, the renumbering of the EU Treaty and the EC Treaty in line with the tables of equivalences in the annex to the Treaty of Amsterdam.
There is a wide array of measures to improve protection of fundamental rights. A procedure was incorporated in the EU Treaty for the imposition of sanctions on Member States that seriously and persistently violate the principles of liberty, democracy, respect for human rights and fundamental freedoms, and the rule of law. The ECJ was expressly awarded jurisdiction within the scope of its competency to review acts adopted by the institutions in the light of fundamental rights. A horizontal clause was incorporated in the EC Treaty, according to which, in all its activities, the Community must aim to eliminate inequalities and to promote equality between men and women. A legal basis for action to combat discrimination based on sex, racial or ethnic origin, religion or belief, disability, age or sexual orientation was also inserted in the EC Treaty. Provision was made for the establishment of a special supervisory body responsible for monitoring compliance with data protection by Community institutions and bodies. The Treaty of Amsterdam granted citizens of the Union the right to write to any of the EC institutions in one of its official languages and to have an answer in the same language. A right of access to European Parliament, Council and Commission documents was also acknowledged.
The three-pillar structure of the European Union was maintained. Since the Treaty of Amsterdam version, however, the third pillar consisted only of provisions on police and judicial cooperation in criminal matters. The other topics were moved (‘communitized’) to a new Title IV of the EC Treaty, which was headed ‘Visas, asylum, immigration and other policies related to free movement of persons’. An area of freedom, security and justice was to be progressively established. The Protocol integrating the Schengen acquis into the framework of the European Union, which was annexed to the Treaty of Amsterdam and relates to the abolition of checks at common borders, is also relevant in this context. The competences of the European Court of Justice in the scope of the new Title IV of the EC Treaty were regulated in a specific provision (European Court of Justice).
One focus of the Treaty of Amsterdam was social policy. The provisions of the agreement on social policy were integrated into the EC Treaty and developed further. The purpose of a new title in the EC Treaty was to develop a coordinated strategy for employment. The Treaty of Amsterdam also laid emphasis on environmental, consumer and health protection. It integrated the principle of sustainable development into both the EU Treaty and the EC Treaty and made environmental protection the subject of a horizontal clause. A high level of protection was prescribed in the areas of health, safety, environmental protection and consumer protection with regard to measures to realize the internal market. The Amsterdam Treaty took into account the special place occupied by services of general economic interest by inserting a provision of its own.
The co-decision procedure was simplified and its scope of application considerably broadened. Consequently, in the field of legislation, in most areas the same weight was attributed to the European Parliament as to the Council. The Amsterdam Treaty also strengthened the role of the European Parliament in the investiture of the Commission. It limited the future number of members of that Parliament to 700. The scope of qualified majority voting in the Council was considerably expanded. The Council was given competency to extend by a unanimous decision the commercial-policy jurisdiction of the EU to international agreements on services and intellectual property insofar as they are not yet covered by the rules applicable. The President of the European Commission was granted a political leadership role in nominating members of the Commission and in the Commission’s activities.
In the context of the second pillar of the treaty (Title V of the EU Treaty) the Treaty of Amsterdam created the office of High Representative for the common foreign and security policy. It equipped the CFSP with a new instrument in the form of common strategies to be decided by the European Council. Humanitarian and rescue tasks, peace-keeping tasks and tasks of combat forces in crisis management, including peacemaking, were expressly included in the CFSP.
The remaining provisions of the third pillar on police and judicial cooperation in criminal matters (Title VI of the EU Treaty) were made much more precise and given a considerably improved structure. This cooperation was then to extend to combating racism and xenophobia. In the field of police cooperation the Treaty of Amsterdam expanded the role of Europol. It defined elements of judicial cooperation in criminal matters as, inter alia, facilitating extradition between Member States and progressively adopting measures establishing minimum rules relating to the constituent elements of criminal acts and to penalties in the fields of organized crime, terrorism and illicit drug trafficking. The Council of the European Union was granted the power, in particular, to adopt framework decisions for the purpose of approximation of the laws and regulations of the Member States. The competences afforded to the ECJ in relation to Title VI of the EU Treaty were covered by a specific provision (European Court of Justice).
To replace rudimentary provisions of the Maastricht Treaty on special cooperation between the Member States, detailed provisions on closer cooperation were included in both the EU Treaty and the EC Treaty. They enabled a smaller number of Member States to press on with integration provided that certain conditions are satisfied.
One of the protocols to the Treaty of Amsterdam is devoted to the application of the principles of subsidiarity and proportionality. The Protocol on the role of national parliaments in the European Union laid down rules for the provision of information to the parliaments of the Member States and endorsed the role of the Conference of European Affairs Committees (COSAC) which had been established in 1989. Mention should lastly be made of the Protocol on the institutions with the prospect of enlargement of the European Union. This provided that the Commission, on which the larger Member States each had two members, was to comprise, at the date of entry into force of the first enlargement of the Union, one national of each of the Member States, provided that the weighting of the votes in the Council had been modified in a manner acceptable to all Member States by that date.
3. Treaty of Nice and the accession treaties on eastward enlargement
Preparations by the institutions of the European Union to manage their tasks in an expanded Union were pursued in the Treaty of Nice, adopted politically at the Nice European Council on 11 December 2000 and signed on 26 February 2001 ( OJ C80/1). The Irish people rejected the treaty in May 2001 in a referendum with a low turnout and did not agree to it until a second referendum was held in October 2002. It came into force on 1 February 2003.
The Treaty of Nice consists of two parts. The first contains substantive amendments relating, in particular, to the EU Treaty and the EC Treaty, whilst the second contains transitional and final provisions. Four protocols were annexed to the treaty, including the Protocol on the enlargement of the European Union, which contains provisions on the European Parliament, on the weighting of votes in the Council and on the Commission, some of which were to apply as from 1 January 2004 and some from 1 January 2005. Declarations 20 and 21 annexed to the treaty stated the common position to be adopted by the Member States at the accession conferences as regards, inter alia, the distribution of seats at the European Parliament and the weighting of votes in the Council. The Treaty concerning the accession of the Czech Republic, the Republic of Estonia, the Republic of Cyprus, the Republic of Latvia, the Republic of Lithuania, the Republic of Hungary, the Republic of Malta, the Republic of Poland, the Republic of Slovenia and the Slovak Republic to the European Union ( OJ L236/16), which was signed on 16 April 2003 and entered into force on 1 May 2004, amended this set of rules in certain respects but without affecting the new approach as such.
For the Council a new weighting of votes was agreed, to be achieved by increasing the number of votes for all Member States whilst at the same time raising to a greater extent the number of votes for the Member States with the largest populations. When a decision was to be adopted by the Council by a qualified majority, a member of the Council could request verification that the Member States constituting the qualified majority represent at least 62 per cent of the total population of the Union. If that should not be the case, the decision in question should not be adopted. The scope of qualified majority voting in the Council was again greatly expanded. In the future the Commission will include just one national of each of the Member States. As from the date on which the first Commission following the date of accession of the 27th Member State of the Union takes up its duties, the number of members of the Commission will be less than the number of Member States, with the precise number being determined by the Council, acting unanimously. The Member States nominate the President of the Commission by a qualified majority; his role has been further enhanced. The maximum number of members of the European Parliament was increased to 732 and its compo-* sition was redetermined. The rules on Community courts underwent wide reform so as to bring the internal organization of the ECJ in line with the larger number of judges and to counter congestion (European Court of Justice). The ECJ can now be awarded jurisdiction over disputes relating to Union industrial property rights. The provisions on enhanced cooperation were made more flexible.
In addition to these reforms the Treaty of Nice brought about a number of other innovations. It inserted in the EU Treaty an early warning system for breaches by a Member State of the principles of the European Union. It incorporated a Social Protection Committee in the EC Treaty. It also conferred authority for regulations governing political parties at European level. Under the CFSP it relinquished the link with the western European Union; it gave a central role to a Political and Security Committee in crisis management operations. The provisions on police and judicial cooperation in criminal matters were supplemented by a passage on Eurojust, the European Judicial Cooperation Unit in criminal matters.
The Treaty concerning the accession of the Republic of Bulgaria and Romania to the European Union ( OJ L157/11) which was signed on 25 April 2005 and entered into force on 1 January 2007, adjusted the EU Treaty and the EC Treaty in line with that expansion.
4. Treaty establishing a Constitution for Europe and the Treaty of Lisbon
The Treaty establishing a Constitution for Europe signed on 24 October 2004 ( OJ C310/1) combined the EU Treaty and the EC Treaty into one single document. It did not enter into force, however. The Treaty of Lisbon amending the Treaty on European Union and the Treaty establishing the European Community ( OJ C306/01) which was signed on 13 December 2007 and entered into force on 1 December 2009 amends both treaties whilst adopting essential elements of the Constitutional Treaty and renames the EC Treaty the ‘Treaty on the Functioning of the European Union’ (TFEU) (European Constitution). The EU Treaty as amended by the Lisbon Treaty, the TEU (2007), is arranged as follows: Title I Common provisions, Title II Provisions on democratic principles, Title III Provisions on the institutions, Title IV Provisions on enhanced cooperation, Title V General provisions on the Union’s external action and specific provisions on the common foreign and security policy, Title VI Final provisions. The provisions of former Title VI on police and judicial cooperation in criminal matters were replaced by provisions in the TFEU. On the other hand, various provisions from the EC Treaty under ‘Principles’, ‘Institutions of the Community’ and ‘General and final provisions’ were replaced by provisions in the EU Treaty (2007) (European Union).
Hans Smit and others (eds), Smit & Herzog on The Law of the European Union (2005); Anthony Arnull and others, Wyatt and Dashwood: European Union Law (5th edn, 2006); Joakim Nergelius, The EU Constitution in a Comparative and Historical Perspective: An Analysis of the Lisbon Treaty and its Importance (2009); Rudolf Geiger, Daniel-Erasmus Khan and Markus Kotzur, EUV/AEUV (5th edn, 2010); Carl Otto Lenz and Klaus Dieter Borchardt (eds), EU-Verträge, Kommentar nach dem Vertrag von Lissabon (5th edn, 2010); Allan Rosas and Lorna Armati, EU Constitutional Law (2010); Christian Callies and Matthias Ruffert (eds), EUV/AEUV, Kommentar (4th edn, 2011); Fernando Díez Moreno, Manual de derecho de la Unión europea (5th edn, 2011); Eberhard Grabitz and Meinhard Hilf (eds), Das Recht der Europäische Union (43th edn, 2011); Koen Lenaerts, Piet van Nuffel and Robert Bray, Constitutional Law of the European Union (3rd 2011).