Priority and Direct Effect
The relationship between EU law and national legal systems was regulated for the first time in the Treaty of Lisbon. This was done not through a specific Treaty provision, but by a declaration annexed to the Final Act of the Treaty. This reflects the issue’s politically sensitive nature. In practice, however, the Court of Justice had declared the principle of the priority of EU law over national law nearly fifty years earlier. In its judgment in Costa v ENEL, handed down in 1964, the Court stated that:
The transfer by the States from their domestic legal system to the Community legal system of the rights and obligations arising under the Treaty carries with it a permanent limitation of their sovereign rights, against which a subsequent unilateral act incompatible with the concept of the Community cannot prevail.3 
The principle of precedence of EU law was thus established. The Court of Justice later noted, inter alia, that EU law takes precedence even over Member States’ constitutions, and prevents the adoption of national legislation that is contrary to EU law.39 This has understandably given rise to considerable discussion and even criticism. Among others, the German Constitutional Court has declared that the condition for its acceptance of the principle of EU law’s precedence is that this law maintains adequate protection of human rights for citizens. 
Closely linked to the question of the primacy of EU law over domestic law is the question of whether EU law may have direct effect, that is, whether it can be invoked by individuals and companies and be applied by the national courts and authorities, with no previous transposition into national law. EU law is basically a part of international law and from this perspective it is up to each State to define whether and how international agreements shall be applied in the respective national legal system. It is therefore far from obvious that such agreements can directly create any rights for individuals or companies in State Parties without making a detour via national law. However, in van Gend en Loos, the Court held that an article in the then EEC Treaty could—and should—be directly applied by a national court. The Court of Justice found that:
the Community constitutes a new legal order of international law for the benefit of which States have limited their sovereign rights albeit within limited fields, and the subjects of which comprise not only the Member States but also their nationals. Independently of the legislation of Member States, Community law therefore not only imposes obligations on individuals but is also intended to confer upon them rights which become part of their legal heritage.41
For a provision of EU law to have direct effect, it is generally required that it is unconditional, that is, does not require any additional measures to be taken, and that it is sufficiently clear and precise. The latter, however, has not prevented provisions whose correct application has occasioned extensive interpretation by the Court from having direct effect. Examples are Articles 34—36 TFEU on the prohibition of quantitative import and export restrictions and the principle of non-discrimination in Article 18(1) TFEU. The case van Genden Loos was about what is usually referred to as vertical direct effect, that is to say a provision of the Treaty that gives individuals a right which they can invoke against the State. There are, however, also examples of horizontal direct effect where such a provision can be invoked in a legal relationship between individuals.^
That regulations can have direct effect is not surprising because, according to Article 288 TFEU, they are directly applicable in each Member State. Directives, however, have in principle no legal effect until they have been transposed through national legislation. The Court of Justice has, nevertheless, relied on the argument of the purpose of a directive and developed the principle that directives can under certain circumstances have direct effect.43 This has been justified by, inter alia, a desire to ensure the effect of directives and to prevent Member States from taking advantage, in relation to individuals, of their own failure to implement a directive in a timely and proper manner.44 The principle has since been developed and expanded through a number of rulings by the Court. Diverse variants or related principles have also been added.45
Direct effect of directives in the strict sense means that a specific provision of a directive can be invoked by individuals before national courts without that provision having been transposed or correctly transposed into national law. For a provision of a directive to have direct effect, it is required that the following conditions are met: (a) the deadline for the implementation of the directive through national action has expired; (b) the Member State has not transposed the directive or has not transposed it properly; (c) the rights and obligations arising from the provision of the directive are unconditional and require no further action from either EU or national authorities; (d) the provision is sufficiently precise to be invoked by individuals and applied by the national courts.46
Against individuals or companies, provisions of a directive can only create rights.47 The principle of legal certainty precludes directives from imposing obligations. An individual cannot rely on a directive against a Member State when it concerns a State’s obligation directly linked to the performance of another obligation that according to the directive belongs to third parties.4® ‘The State’ has in this context been broadly interpreted by the Court of Justice, and ‘individual’ has therefore got a narrow definition.    
As regards environmental directives, examples of rules which have direct effect can be found in, among other places, directives with specific provisions relating to limits on emissions or to quality standards. The Court has declared that in all cases where Member States have failed to take action required by a directive on air quality or drinking water quality—the aim of which is to protect human health—and have thereby jeopardised individuals’ health, everybody is entitled to invoke the mandatory provisions of these directives.50
Court practice has, however, loosened up the requirement that a directive must specifically give rights to individuals so that it can be invoked by them before national courts. In the Kraaijeveld case,5i the Court said that certain provisions of Directive 85/337/EEC on the assessment of the effects of certain public and private projects on the environment (EIA Directive^2 could be invoked to override a national measure even though the rules of the Directive were conditional and gave no clear right to individuals. It can of course be discussed whether the decision in this case involves application of the principle of direct effect or another particular effect of a directive, for example supremacy of the EU law. This type of application of a directive, confirmed in subsequent Court practice, has been accepted mainly in relationships between individuals. This may be because the Court applies different requirements when examining the compatibility of a national rule with a directive compared to when it assesses the direct application of a directive in relation to individuals. However, the result of inability to apply a national rule may very well be to worsen an individual’s situation from a legal point of view. In the Delena Wells case, the Court made it clear that ‘adverse repercussions on the rights of third parties’ do not justify preventing an individual from invoking the provisions of a directive against a Member Stated3 In this case, extraction in a quarry had to cease in anticipation of an environmental impact assessment that the Member State had, in breach of Directive 85/337, failed to require from the owner of the business before granting the licence.
The same line of argument was applied by the Court in another case that concerns the relation between two public entities. The Salzburger Flughafen case54 is about the application of the EIA Directive to a projected extension of Salzburg Airport. When the airport operating entity submitted an application to the relevant permit authority, the Amt der Salzburger Landesregierung (the Amt), another public entity, the Landesumweltanwaltanschaft Salsburg (Legal Office for the Environment), requested the Amt to include an EIA requirement in the permit.
The Amt rejected this request. The decision was appealed against and the Austrian Supreme Administrative Court eventually requested a preliminary ruling from the Court of Justice. The latter confirmed that the relevant provisions of the EIA Directive have direct effect without discussing the fact that the directive had been invoked not by an individual, but by one public authority against another. This implies that provisions of a directive may be invoked against a Member State not only by individuals who derive rights from those provisions, but also by branches of the State itself, and even when that has repercussions for third parties.55
Alongside the direct effect of directives, there is a far-reaching obligation for national courts to attempt to achieve the purpose of a directive by interpreting national law in the light of the directive. This rests on a general obligation for courts to interpret national law so that it complies with EU law.56 The Court has expressed that the principle of consistent interpretation requires that ‘the national court does whatever lies within its jurisdiction’ to ensure that a specific directive is given its full effect.57 The legislation need not be interpreted against its express letter.
If a national legal system, despite the above principles of priority, direct effect, and interpretation, does not correctly reflect European legislation and this is detrimental to an individual’s interests, the State may become liable to pay damages to the individual in accordance with the so-called Francovich principled8
A relevant question is whether a Member State is obliged to take account of a directive’s objective before the time for its transposition into national law has expired. The Court stated in the Inter-Environnement Wallonie case regarding the interpretation of a waste directive that during the period laid down in the directive for its implementation, Member States must refrain from adopting measures liable seriously to compromise the result prescribed^9
In summary, the Court, through its practice, which in itself is hardly clear and precise, has developed extensive opportunities for individuals to bring about a review of national legal compatibility with the provisions of EU directives, whether or not a directive contains rights for individuals. However, as regards the environment, this opportunity has been partly offset by directives that are increasingly designed as a framework without clear goals and standards. This makes it harder to control their application and assess whether Member States’ actions are in compliance with EU law.      (See further Chapter 6.)
As further discussed in Chapter 5, Member States have a general obligation to provide remedies sufficient to ensure effective legal protection in the fields covered by Union law. (Art 19 (1) TEU) This has implications for individuals’ possibility to initiate a judicial review and make use of the principle of direct effect.