Preliminary ruling

A preliminary ruling is a decision of the European Court of Justice (ECJ) on the interpretation of European Union law, made at the request of a court or tribunal of a European Union member state. Preliminary rulings are final determinations of Union law in question by the EU courts. The final decision remains with the referring court to be decided after it received the preliminary ruling. European Union preliminary rulings can only be made by the European Court of Justice. The Treaty of Lisbon provided that jurisdiction may be conferred on the General Court, but this has not been put into effect.

A request (or reference) for a preliminary ruling is made by submitting questions to the ECJ for resolution. However, questions are not answered in abstraction, but rather are submitted together with the circumstances leading up to their being asked. Thus, whilst the ECJ is limited to deciding the law in question, the ECJ's ruling frequently leaves little room to rule other than in a certain way. The ECJ may also decline to give judgement in the absence of a genuine dispute.

Article 267 of the Treaty on the Functioning of the European Union states the following:

What constitutes a "court or tribunal" is a matter of Union law and it is not to be determined by reference to national law. In determining whether or not a body is a "court or tribunal of Member State" the European Courts will take a number of issues into account, namely whether—

However, these criteria are not absolute. In Broekmeulen v Huisarts Registratie Commissie the ECJ ruled that a body established under the auspices of the Royal Medical Society for the Promotion of Medicine was a "court or tribunal" within the meaning of the treaty, even though that society was a private association. Also the Benelux Court of Justice was considered a court within this context, as a court common to several (Netherlands, Belgium, Luxembourg) Member States. Also the Unified Patent Court, as a court common to several Member States is expected to be able to ask prejudicial questions.

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