Pathfinder to European Union Law

Bryan van Pottelsberghe de la Potterie
Law Library Fellow (updated March 2018)


This is a selective guide to conducting research on European Union Law. It is arranged in five sections. Part I presents the researcher with the various European Union treaties. Part II is devoted to the European Judicial system and key cases. Part III revolves around the institutions and information found within their websites. Part IV is a list of useful legal databases found within the European Union's official online portal. Finally, Part V is a list of recommended third party websites devoted to further guiding researchers through European Union law.

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The European Union is a social, economic and political union made up of twenty-seven Member States. From its original composition of six countries in the 1950s (France, Belgium, Luxembourg, the Netherlands, Germany and Italy), the EU has grown to its present size and makeup through a series of enlargements: Ireland, the United Kingdom and Denmark (1973); Greece (1981); Spain & Portugal (1986); Austria, Sweden and Finland (1995) and the enlargement of May 2004, which added ten new members, mainly former communist bloc countries: Czech Republic, Estonia, Cyprus, Latvia, Lithuania, Hungary, Malta, Poland, Slovenia and Slovakia. Bulgaria and Romania were added in January 2007.

By joining the European Union, the Member States agree to be bound by certain policies developed by the European Union in its attempt to harmonize trade, movement of goods and people, security and in other policy areas designated by the treatises. Some states have also agreed to enter into a common monetary policy for which the Euro is the official currency. The European Union is composed of five main governing institutions: the Commission, the European Council, the European Parliament, the European Court of Justice and the Court of Auditors.

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Part I: Treaties

Currently, what may be considered as a European Constitution consists of a series of major treaties. The treaties are considered primary law. The date of signing varies from the date a particular treaty came into effect, as a treaty must be ratified by each member state before it becomes law. Following below, in chronological order from most recent to latest, are links to the major treaties. Many of the following treaties are excerpted from the treaties portion of the  Europa website.

  • Lisbon Treaty—The path to the final version of this document was a rocky one. Beginning in 2002, attempts were made to create a constitution-like document for the Union encapsulating the spirit of the treaties entered into by its members. By 2004, agreement was reached on a final version which was to have been ratified by all Member States under their respective constitutional processes. Following rejection of the constitution in France and the Netherlands, EU governing bodies requested a pause in the process of ratification and planned further discussions for 2006. In 2009 the new Lisbon Treaty was finally approved by all EU member countries and set to go into effect on January 1, 2010 (it may become effective on December 1, 2009 if the final country to ratify, the Czech Republic, submits its document to Rome in November 2009).
  • The Treaty of Nice—Signed in February 2001, the treaty made reforms to the European Union's institutions. With the impending enlargement of the European Union from a number of Baltic and Eastern European states, institutional adaptations were necessary for effective governance of the Union. This was accomplished by amending previous treaties.
  • The Amsterdam Treaty—Signed in October 1997, the treaty that emerged touched upon many economic and social issues impacting the Union but failed to restructure the political organization as would be needed with the arrival of new states.
  • The Treaty of Maastricht (European Union)—For the first time the term European Union became the official name of the economic and social pact made between the Member States. This is also where the term the three pillars was used to describe the new structure created by the treaty. These three structures constituted a: (1) European Community, (2) common foreign and security policy, and (3) justice and home affairs. The treaty also set criteria for establishing a single European currency.
  • The Single European Act—Signed by the original six members in 1986 as well by new members, Great Britain, Spain, Ireland, Portugal and Denmark, the treaty revolved around creating a common market by dismantling the remaining fiscal, physical and technical hurdles to economic conformity.
  • 1965 Merger Treaty—The treaty effectively created the modern day European Commission and the European Council. The European Commission took the place of the former three separate commissions: the High Authority of the European Coal and Steel Community, the Commission of the European Economic Community and the Commission of the European Atomic Energy Community. The European Council took the place of former three separate councils: the Special Council of Ministers of the European Coal and Steel Community, the Council of the European Economic Community and the Council of the European Atomic Energy Community. Note: not available in English.
  • Treaty of Rome—In 1955, the Treaty of Rome was signed creating the European Community, the precursor to the European Union. This treaty was signed by the same six members as the earlier Treaty of Paris. It established the European Economic Community and the European Atomic Energy Community. Economic harmonization and a commitment to future political integration were its central tenets. At its heart lay the concept of a Common Market for the free passage of goods and labor throughout the Member States.
  • Treaty of Paris—The idea of the European Union began life under the Treaty of Paris, which established the European Coal and Steel Community. The treaty was signed on April 18, 1951, by the countries of Germany, Belgium, Luxembourg, France, the Netherlands, and Italy and was the first iteration in the goal of creating a united Europe. It created a supranational organization delegated to harmonize coal and steel prices within the union.

A brief description of the treaties as well as the negotiations and drafts leading to the various final treaties may be found at the University of Zaragoza.

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Part II: Judiciary

The judicial branch of the European Union is composed of the European Court of Justice, Court of First Instance and the Court of Auditors. They are based in Luxembourg. Additionally, in limited circumstances, Member States may rule on EU law matters. Member State decisions may also constitute a part of precedence in EU law.

  • European Union Case Law—The above case law is for the European Court of Justice and Court of First Instance. Cases after June 1997 may be accessed either by: case number, date, name(s) of parties, fields, or words in text. Cases before June 1997 may be found either through case number or by case name by scrolling to the top of the case list and hitting CTRL+F and entering a name.
  • European Court of Justics (ECJ)—The supreme court of the European Union is made up of fifteen judges and eight advocates general. One judge is selected by the others to act as President of the Court for a three year term. The judges and advocate generals are appointed by the common accord of the Member States and remain in office for a renewable six year term. Depending on the case, the court may sit in plenary, a Grand Chamber of 13 or in chambers of three to five judges. The court reviews cases pertaining to the interpretation of the European Union treaties and laws enacted by the European Union institutions. Some of the areas for which the court has jurisdiction include: cases brought against Member States by the Commission for failure to meet a specific EU obligation, preliminary rulings on EU law in cases before Member States' courts and appeals from the Court of First instance. Please see the Introduction section in the above link for additional jurisdictional areas of the court. Direct link to case searching for both ECJ and CFI is here.
  • Court of First Instance—Similar to the ECJ, the Court is composed of fifteen judges but does not have any advocates general. The court was established to reduce the volume of cases appearing before the ECJ. A simple analogy is the role the of Circuit and District courts in the United States. While in many respects the ECJ primarily handles issues dealing with the Member States and European institutions, the Court of First Instance regularly deals with cases brought by legal persons or entities against the European Union institutions. The Court of First Instance homepage and cases are located within the same page(s) as the European Court of Justice.
  • European Court of Auditors—The Court of Auditors audits the collecting and spending of funds by European Institutions. The Court reports its results in opinions and annual reports.

Key European Union Cases

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Part III: Institutions

  • European Commission—The Commission consists of twenty-five members--one from each Member State--and functions both as an executive and legislative entity for the EU. It is headed by a President, who is appointed by the governments of the Member States and approved by the EU Parliament, and commissioners, each of whom handles a designated portfolio concerning economic and social policies. On the legislative end, it is empowered to create new laws. It possesses executive powers by overseeing the implementation of its laws as well as investigating Member States to determine if they have met or failed to adequately enact new laws necessary to fulfill their legal obligations towards their citizens. The site provides links to the various commissioners' departments specializing on a particular policy unit where additional legal information may be obtained. The sites provide information and documents concerning EU regulations, directives, decisions and recommendations.
  • European Council—The Council is a meeting place for the Member State's government representatives. Depending on the occasion and circumstance, Heads of State or ministers may be utilizing the forum to meet and discuss European Union issues. The Council possesses legislative and budgetary powers while handling important international and security issues for the European Union. This is where sensitive international pronouncements are made by the European Union. By following the public register link, the researcher will find a search screen to access the Council's announcements. Note that only decisions published in the Official Journal are legally binding.
  • European Parliament—Members of the European Parliament (MEPs) are directly elected by Member States citizens. Unlike traditional legislative branches, the European Parliament does not have primary authority to introduce new laws, enact laws or have sole control over the budgetary process. These duties must be effectuated in conjunction with either the Commission or the Council depending on the circumstance and issue. Legislative happenings and laws may be perused at EUR-Lex or at OEIL.

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Part IV: Databases 

  • EUR-Lex—The website maintained by the European Union is the main database to access treatises, the Official Journal, Legislation, Case-law, and important documents. The documents are available in the official languages of the European Union.
  • PreLex—Proposed legislation being discussed among the various European institutions may be searched at this database. This includes the formation of budgetary and international agreements.
  • Brief Policy Summaries—An overview of major European Union laws on a particular topic is provided at this link. Select the Index and/or glossary at the top of the page for a more in depth list. Furthermore, the Search tab allows for a more targeted query.
  • Enlargement—This is the EU Commission's page devoted to discussion and issues relating to EU enlargement and the future of the EU.
  • Europa Information by Topic—This is Europa's guide to quickly finding information on a variety of European Union subjects.
  • European Union Open Data Portal- provides oen access to EU law-related datasets.
  • EuroStat—An assortment of European Union statistical data.

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Part V: Research Guides

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Research Category

Foreign Law
Research Guides