“Applying the principle of cooperation laid down in Article 5 of the Treaty, it is the national courts which are entrusted with ensuring the legal protection which citizens derive from the direct effect of the provisions of Community law. Accordingly, in the absence of Community rules on this subject, it is for the domestic legal system of each Member State to designate the courts having jurisdiction and to determine the procedural conditions governing actions at law intended to ensure the protection of the rights which citizens have from the direct effect of Community law, it being understood that such conditions cannot be less favourable than those relating to similar actions of a domestic nature.”
“The aim of this principle is that domestic law remedies should safeguard Community law ‘without discrimination’ that is to say, exercise of a Community right before the national courts must not be subject to conditions which are more strict (for example, in terms of limitation periods, conditions for recovering undue payment, rules of evidence) than those governing the exercise of similar rights derived wholly from domestic law.”
“Observance of the principle of equivalence implies, for its part, that the procedural rule at issue applies without distinction to actions alleging infringements of Community law and to those alleging infringements of national law, with respect to the same kind of charges or dues (see, to that effect, Joined Cases 66/79, 127/79 and 128/79 Amministrazione delle Finanze dello Stato v Salumi [1980] ECR 1237, para 21). That principle cannot, however, be interpreted as obliging a Member State to extend its most favourable rules governing recovery under national law to all actions for repayment of charges or dues levied in breach of Community law.”
“… the principle of ‘equivalence’ really does mean what it says. The domestic court, in applying the principle, must look not merely for a domestic action that is similar to the claim asserting Community rights, but for one that is in juristic structure very close to the Community claim. It does that, in the words of the Court of Justice in Levez v. T H. Jennings (Harlow Pools) Ltd. (Case C-326/96 ) [1999] I.C.R. 521, 545, para. 43, by considering ‘the purpose and the essential characteristics, of allegedly similar domestic actions’.”
“In these appeals, however, the parallel between the statutory right to paid annual leave and a contractual right to holidays with pay is to my mind much clearer and closer. It is not less close because of the Working Time Directive's emphasis on health and safety at work. Similar thinking has for many years informed the approach of responsible employers in framing contractual terms of employment. Moreover in each case the remedy would be an order for payment of the liquidated sum due.”