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A Guide to Researching EU Law

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The following is a guest post by Micaela DelMonte, a lawyer from the European Parliamentary Research Service who volunteered at the Law Library of Congress during May 2017.

News about Brexit and the so-called Article 50 procedure have dominated the news about the European Union (EU) lately. If you are interested in researching these or other EU-related topics, then you have come to the right place. This Guide to researching EU law provides concise information about EU law sources and where to retrieve them.

I. What is EU Law?

On March 25, 1957, the governments of France, Germany, Italy, BelgiumNetherlands, and Luxembourg signed the “Treaties of Rome”, thereby establishing what would later become the EU. The body of common rights and obligations that is binding on the EU Member States is known as the “acquis communautaire.” Within the acquis, the Treaties are considered primary law while the body of law stemming from the principles and objectives established in the Treaties is known as secondary law.

Primary Law

EU primary law consists of the founding Treaties, now after several amendments called the Treaty on European Union (TEU) and the Treaty on the Functioning of the European Union (TFEU), the amending EU Treaties, the protocols annexed to the founding and amending Treaties, as well as the Accession Treaties for new EU Member States. Referred to together as “the Treaties,” these instruments lay down the objectives of the EU, the rules for the EU institutions, and procedures for the adoption of legislative and non-legislative acts. The consolidated versions of the TEU and the TFEU, together with their annexes and protocols, resulted from the latest amendments introduced by the Treaty of Lisbon, which was signed on December 13, 2007, and entered into force on December 1, 2009.

In addition, the Treaty Establishing the European Atomic Energy Community (Euratom Treaty) continues to exist as a separate treaty.

Following the entry into force of the Treaty of Lisbon on December 1, 2009, primary law status was also given to the Charter of Fundamental Right (EU Charter).

Secondary Law

The types of legal acts that the EU may adopt to exercise its competences are listed in article 288 of the TFEU. They are regulations, directives, decisions, recommendations, and opinions. Oftentimes, the Treaties establish which type of legal act should be adopted for a given policy area. When this is not the case, article 296 (1) of the TFEU states that the institutions will decide on a case-by-case basis in compliance with the “principle of proportionality.”

A “regulation” is a binding legislative act that must be automatically and uniformly applied in its entirety by all Member States. A regulation does not need to be transposed into national law. It is directly applicable as soon as it enters into force (i.e., on the date stipulated in the act or, failing this, on the 20th day following the publication in the Official Journal of the European Union.)

A “directive” is a legislative act that determines the main objectives to be achieved by all EU Member States. However, it is up to the individual Member States to define and draft their own laws on how to reach these goals. The Member States adopt measures to transpose the directive into their respective national law. Transposition must take place before a deadline (usually two years) which is set out in the directive and the national measures of implementation have to be communicated to the European Commission.

A “decision” is binding on those to whom it is addressed (e.g., an EU Member State, an individual or a company) and is directly applicable. The party, or parties, must be notified and the decision comes into effect upon such notification. A decision does not need transposition into a national law.

“Recommendations” and “opinions” do not have binding force.

Supplementary Secondary Law

The jurisprudence of the Court of Justice of the European Union (CJEU) is considered supplementary secondary law. The CJEU ensures that EU law is interpreted (preliminary ruling) and applied the same way in each Member State (infringement proceedings against one or more Member States for failing to comply with EU law). It also settles legal disputes between EU national governments and EU institutions. This may happen when an EU law supposedly violates fundamental rights and/or the EU Treaties (actions for annulment), or when the EU institutions are accused of not taking actions that are due (actions for failure to act). Also, under specific circumstances, individuals and business may address the Court.

European Flag. Photo by Flickr user Rock Cohen. April 5, 2008. Used under Creative Commons License 2.0, https://creativecommons.org/licenses/by-nc-nd/2.0/.

II. Online Resources

Primary Law 

  • Treaties currently in force provides consolidated versions of the TEU, TFEU, and Euratom Treaty, as well as the text of the EU Charter.
  • Founding treaties provides the original texts of the treaties from 1951 (Treaty establishing the European Coal and Steel Community) , 1957 (Rome Treaties), and 1992 (Treaty on European Union).
  • Accession treaties provides the texts of agreements between the EU and countries joining the EU as new members.
  • Other treaties and protocols includes, among others, the text of the EU Charter, the Schengen Agreement which led to the creation of Europe’s Schengen Area in which internal border checks have largely been abolished, and various other treaties and protocols.
  • Chronological overview of Treaties lists all the EU Treaties in chronological order.
  • EU Treaty Search

Secondary Law

  • The Official Journal (OJ) of the European Union is published every day from Tuesday to Saturday in 24 official EU languages. There are two main series, L (legislation) and C (information and notices). A subseries CA includes calls for expressions of interest, vacancy notices, etc. CA editions may be published in one, several, or all official languages.
  • EUR-Lex is a database which provides access to EU law (primary, secondary law and also national implementing measures) in the 24 EU official languages. It also provides easily accessible summaries of EU law and policies.
  • The Legislative Observatory is the database of the European Parliament for monitoring the EU decision-making process. It allows research by key words, subject matter, year, type of procedures, type of acts, legal basis etc.
  • The website of the CJEU allows case law search. Alternative search options for EU case-law are also available on EUR-Lex.

Other Web Resources

  • The official documents of EU institutions, consultative bodies, and executive agencies are available online.
  • EU Bookshop is an online bookshop, library, and archive of publications dating back to 1952.
  • Libraries and archives of the EU institutions and digital libraries enable online access to a range of resources.
  • The Historical Archives of the EU are administered by the European University Institute of Florence.

 III. Print Resources

The Law Library of Congress holds a vast print collection of material on EU law. It is also a repository of certain EU publications, including the Official Journal of the EU.

The following blog post highlights some of the many resources on EU law available at the Law Library:

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