Introduction

1. Is it necessary for the Member States, in order to ensure that the health and safety of workers in the workplace is fully and effectively protected — which is an objective pursued by Directive 2003/88/EC by means, inter alia, of the setting of limits on working time — to make it compulsory for employers to introduce systems to measure the actual duration of the working day and working week?
2. That is, in substance, the issue raised by the request for a preliminary ruling, put to the Court of Justice by the Audiencia Nacional (National High Court, Spain), which is the subject of this case. That request arose in the context of a group action brought by a number of trade unions with the aim of establishing, and obtaining a declaration of the existence of an obligation upon the defendant, Deutsche Bank SAE, to set up a system which records the actual number of hours worked daily and makes it possible to check that the working times laid down in legislation and collective agreements are properly adhered to.
3. In this Opinion I shall explain the reasons for which I believe that European Union law does impose an obligation on the Member States to introduce rules governing working time which, subject to the discretion which remains with the Member States as a result of the minimum harmonisation effected by Directive 2003/88, ensure effective compliance with the rules on limits on working time, by way of the introduction of systems that measure work actually done. Indeed, in my view, the absence of such mechanisms from the legal system of a Member State will undermine the effectiveness of that directive.
4. I therefore consider that Directive 2003/88 precludes national legislation which fails expressly to require employers to measure in some way or other or to monitor the ordinary working time of workers in general.

Conclusion

In the light of the foregoing considerations, I suggest that the Court answer the request for a preliminary ruling put to it by the Audiencia Nacional (National High Court, Spain) in the following terms:

1. Article 31(2) of the Charter of Fundamental Rights of the European Union and Articles 3, 5, 6, 16 and 22 of Directive 2003/88/EC of the European Parliament and of the Council of 4 November 2003 concerning certain aspects of the organisation of working time must be interpreted as imposing on undertakings an obligation to set up a system for recording actual daily working time for full-time workers who have not expressly agreed, individually or collectively, to work overtime and who are not mobile workers or persons working in the merchant navy or railway transport workers and precluding national provisions from which no such obligation can be inferred.
2. The Member States are free to determine what method of recording of actual daily working time is best suited to achieving the effectiveness of those provisions of EU law.
3. However, the referring courts must determine, taking the whole body of domestic law into consideration and applying the interpretative methods recognised by domestic law, whether they can arrive at an interpretation of domestic law that is capable of ensuring the full effectiveness of EU law. In the event that it is impossible to interpret national provisions such as those at issue in the main proceedings in a manner consistent with Directive 2003/88 and Article 31(2) of the Charter of Fundamental Rights, it follows from the latter provision that the referring courts must disapply such provisions and ensure that the obligation on undertakings to equip themselves with an adequate system for recording actual daily working time is met.