Enforcement at national level - Focus on the role for national judge in air quality litigation

Effectiveness of EU law

EU law must be applied by the domestic judge because it enjoys precedence over internal law. (Case 6/64 Costa v Enel; Case C 409/06 Winner Wetten, para. 53). National courts are, therefore, required to interpret their national law, to the greatest extent possible, in conformity with the requirements of EU law. This may even result into the change of established case-law, where necessary, if it is based on an interpretation of domestic law that is incompatible with the objectives of a directive (Case C-441/14 DI, para 33).

The meaning and scope of terms for which EU provides no definition must be determined by considering their usual meaning in everyday language, while also taking into account the context in which they occur and the purposes of the rules of which they are part (Case C-184/14 A, para. 32).

Example: In Case C-585/10 Møller, the CJEU noticed that the term 'sow' does not have a univocal meaning in all the official languages. It decided for interpretation which equates gilts with the sows because, for industrial installations which have a significant potential for pollution, both sows and gilts have the same effect on the environment.

While the principle of interpreting national law in conformity with EU law has certain limits and, in particular, cannot serve as the basis for an interpretation of national law contra legem, it nevertheless requires, to the greatest extent possible, that the whole body of domestic law is taken into consideration, and that the interpretative methods recognised by domestic law are applied, with a view to ensuring that EU law is fully effective, and achieving an outcome that is consistent with the objective it pursues. In short, the interpretation also has to ensure that EU law is fully effective (Case C-573/17 Poplawski, para 53-55).

To achieve effective regulation of air quality, the national court should be able to bring the national practice in line with EU legislation.

Example: In Case C-404/13 ClientEarth, the CJEU ruled that the national court should order any measure necessary to bring the air pollution plan into line with EU air quality legislation. In this case, an NGO asked the UK courts to order the government to improve plans required under EU law to reduce dangerous levels of nitrogen dioxide in 16 urban areas, including Greater London. High nitrogen dioxide levels affect the health of millions of British people, especially vulnerable groups such as children and old people. The first UK court ruled that it was not its business to order the government to improve air quality measures but the UK Supreme Court sought guidance from the CJEU which confirmed it is (also) up to the national courts to achieve effectiveness of the EU law.

The role of the National Judge in the European Judicial System and the Procedures of the CJEU

Effectiveness of EU law