Abstract

The article is concerned with the issue of collaboration of national courts with ECJ basing on the procedure of prejudicial query, which is regulated in Art. 267 of the Treaty on the Functioning of the European Union. Taking into account ECJ judgments and rules of national law, the author analyzed the definitions of a court whose decisions are not appealable in accordance to domestic legislation, at the same time indicating the need to adopt the concrete theory. What is important is that when a cassation appeal is allowed in a given case, it is the Supreme Court whose decisions are not appealable. In author’s opinion the legal assessment of a court of a higher instance concerning EU law is not binding for a court of a lower instance, since no national court may be deprived of an opportunity to address a prejudicial query to ECJ. However, the duty to file a prejudicial query is not of an absolute nature, since applying theacte clair or acte éclairé doctrine a national court may effectively relieve itself from this duty.