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EU treaties

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The EU is based on a series of international legal agreements between its member states, called treaties, which set out the ground rules for how the EU is run, its long-term goals and the powers it has. The EU can only act in line with these treaties. The first treaty, which established the European Economic Community (EEC), was signed in Rome in 1957. There have been five subsequent treaties – the Single European Act (1986), the Treaty of Maastricht (1992), the Treaty of Amsterdam (1997), the Treaty of Nice (2001) and the Treaty of Lisbon (2007). Each treaty has amended the basic rules of the EU to introduce new areas of cooperation between member states.

The Treaty of Rome (1957)
The Treaty of Rome was the founding treaty of the European Economic Community (EEC), which later became the EU. The Treaty established that the EEC would be governed by four institutions – a Commission, a Council of Ministers, the European Parliament and the European Court of Justice. The Treaty aimed to create closer cooperation on a range of economic and trade issues from agriculture to overseas aid, commerce to taxation. It proposed a common market of goods, workers, services and capital (money) as one part of a wider vision for unity and cooperation within Europe.

After the Treaty of Rome was signed the EEC underwent a series of changes until the treaty was significantly amended in 1986. First, the EEC merged with the European Coal and Steel Community (ECSC) and the European Atomic Energy Community (EURATOM) to become the European Communities in 1967. The Commission and Council, established by the Treaty of Rome, now had authority over all three.

Membership of the European Communities expanded with Denmark, Ireland and the UK joining in 1973; Greece in 1981; and Spain and Portugal in 1986. The European Parliament, whose members had previously been appointed, was directly elected for the first time in 1979. The treaty had also set out the aim for a Common Fisheries Policy (CFP) and in 1970 a regulation was drawn up which gave members equal access to fishing waters. In 1983, the CFP was formally established to control fish stocks, vessels, market regulation and external agreements.

The Single European Act (1986)
The Single European Act (SEA) was the first major attempt made by member states to amend the Treaty of Rome. The SEA laid the groundwork for the creation of a single market by 1992. It grew out of member states’ frustrations that their trade with other members was limited because their laws were not yet harmonised. They also felt that if cooperation between members was improved, especially in science and technology, Europe could compete better against the US and Japanese economies.

Harmonising laws had been difficult due to slow decision making in the Council, since it required member countries to agree unanimously to any changes in the law.  To resolve this, the SEA introduced qualified majority voting (QMV) so that one country could no longer block suggested changes, making it easier to pass new laws. The SEA removed restrictions in a range of areas of private enterprise, as well as in the public sector. It also strengthened the power of the Parliament and laid the basis for a European foreign policy.

The Treaty of Maastricht (1992)
The Maastricht Treaty widened the European Community’s responsibilities and created the European Union (EU) to replace the EEC. The treaty amended the Treaty of Rome and advanced the agenda set out under the Single European Act to extend member states’ cooperation, from economic and social affairs to political policies such as foreign affairs and justice. It introduced a model for this new Community based on three pillars. The former EEC became the economic relations pillar, with foreign policy, and justice and home affairs forming the other two. To further improve economic harmony it set out to create a single European currency called the euro and a timetable for members to join. It also introduced a number of social policies such as workplace safety regulations and gender equality.

The Treaty of Amsterdam (1997)
The Treaty of Amsterdam set out to simplify and tidy all the preceding treaties.  The treaty tried to lay down a framework for adding ten new member states, mainly from Eastern Europe, by reforming the institutions. It absorbed the Schengen Convention, which removed border controls between 12 of the member states, into EU law and also allowed the EU to legislate on immigration if freedom of movement was affected. It expanded the role of the Common Foreign and Security Policy (CFSP) by creating a High Representative to take overall responsibility for EU foreign affairs and act as the face of Europe on the world stage. Once again further cooperation was brought about by expanding the number of decisions covered by qualified majority voting (QMV) to 14 new areas of policy. Many of the rules introduced by the Amsterdam Treaty were viewed as insufficient or unworkable and required revision by later treaties.

The Treaty of Nice (2001)
The Treaty of Nice was a further attempt to find a way to progress European integration and expansion by giving a framework for a Union of 27 member states. Much of the text of the treaty was concerned with adapting the institutions to be able to cope with the addition of these new members.  QMV was extended in the Council to a further 27 policy areas ; it changed the way in which the Commission President is elected; gave the President the power to sack individual Commissioners; capped the future number of MEPs to 732; and put plans in place to reduce the number of Commissioners once there were 27 member countries. Finally, it declared that another inter-governmental conference should be set up to draft an EU constitution. The treaty was criticised for failing to sufficiently reform the EU institutions, and for failing to incorporate the Charter of Fundamental Rights (CFR).

The Treaty of Lisbon (2007)
The Lisbon Treaty was drafted to complete the reforms started by the Amsterdam and Nice Treaties. It also resolved issues surrounding the EU Constitution, drawn up after the Nice Treaty, after it was rejected by France and the Netherlands. Instead of a new constitution, the Lisbon Treaty amended the previous treaties to reform the institutions.  The Treaty abolished the pillar structure set out in the Maastricht Treaty, clarified the role of European bodies, made explicit the aims of the EU and strengthened measures to achieve these goals.

As such, it changed the way EU decisions are made. It expanded the areas in which the Commission can propose legislation and made QMV the default voting method in the Council, meaning that 55% of member states representing 65% of the EU’s population became a majority. It gave the EU legal independence to sign international agreements in its own name. The Parliament was strengthened, making it equivalent to the Council of Ministers in the process of passing laws and it gained the power to approve the appointment the President of the Commission. The treaty also created a President of the European Council to represent the EU as a whole on the world stage. It also resolved the issue left over from the Nice treaty by adopting the Charter of Fundamental Rights (CFR) into European law (Poland, the UK and the Czech Republic opted out from the implications of the CFR). Lastly, the treaty outlined a procedure for states to end their membership of the EU for the first time.

Following the financial crisis in 2008 several eurozone countries (Greece, Portugal, Ireland, Spain and Cyprus) were unable to bail out their banks or repay government debts. As a result, a further treaty was signed by eurozone members to establish the European Stability Mechanism (ESM) organisation in 2012. This set up a fund to provide bailouts to members, with a maximum lending capacity of €500 billion. This was followed by the Fiscal Compact, signed in 2013, which further coordinated eurozone members’ fiscal policies. Although the compact is not an official EU treaty, it was signed by 25 of the 27 members and plans are in place to incorporate the compact into EU law by 2018.