Principles of legitimate expectations and legal certainty in the context of amendments to EU law and national legislation

Abstract

This paper concerns selected problems related to the complex topic of changes to the EU law and national legislation. It deals with the so-called prior effectiveness of the EU directives and the retroactivity of (ordinary) laws adopted by the EU member states. The research perspective focuses on the functioning of these institutions vis-à-vis the principles of legitimate expectations and legal certainty. The article is primarily based on the analytical method, as well as the empirical method, drawing on the extensive case law of the Court of Justice of the European Union and the Supreme Administrative Court in Poland. Based on the research carried out by the author, it must be concluded, firstly, that an EU directive during its transposition period in an EU member state cannot be a source of legitimate expectations of an individual. Secondly, the principle of legal certainty is not negated when a normative act receives retroactive effect by way of an exception in order to protect the public interest, provided that legitimate expectations of individuals are guaranteed.