This article aims at establishing how national courts interpret the concepts of mitigation and compensation measures under Article 6 of the Habitats Directive. Based on a comparative method of legal research, we focus on the implementation of Articles 6(3) and 6(4) of the Habitats Directive, as interpreted by the Court of Justice of the European Union in the Sweetman, Briels and Orleans cases, and its application in the courts of six Member States, i.e. France, Germany, the UK, the Netherlands, Italy and Bulgaria. Our study highlights national courts tendency to interpret the Habitats Directive and related national law so as to cover matters which have not explicitly been dealt with by the CJEU without asking for preliminary rulings. In each legal order, this lack of preliminary references comported a wrongful interpretation of Article 6(3) of the Directive. This finding shows that the lack of preliminary references affected the legal effectiveness of Article 6 HD.
European Energy and Environmental Law Review