The effects of a preliminary ruling of the European Court of Justice

One of the significant competences of the European Court of Justice is to issue a preliminary ruling on an issue which has been referred to this Court by the national courts of the EU Member States. In this procedure, the national courts are provided the necessary explanation on the applicable EU law, either through by interpreting some legal provisions or by assessing the validity of a legal act adopted by the EU institutions. The preliminary ruling of the Court of Justice is binding for the national court which referred the issue to the Court. The decision is also binding for all national courts which have jurisdiction to decide on legal remedies in this matter. On the other hand, the effect of the preliminary ruling on other national courts is not quite clear. In other words, there is a dilemma as to whether the preliminary ruling on a disputed issue posed in one proceeding is binding for all other courts, which have not been actually involved in this particular proceeding. As for the temporal effect of a preliminary ruling, there is a general rule that the Court's preliminary ruling has a retroactive effect. However, in some situation, the Court of Justice may limit the retroactive effect of its rulings if their ex tunc application is incompatible with the principle of legal certainty.