In its Judgment of 20 December 2017 in Global Starnet, C-322/16, EU:C:2017:985, the Court of Justice of the European Union (CJEU) followed the Opinion of AG Wahl and clarified that a national court of last instance is under an Art 267 TFEU obligation to refer a question for preliminary ruling to the CJEU even if the constitutional court of that Member State has already assessed the constitutionality of national rules in the light of regulatory parameters with content similar to rules under EU law.
The case concerned the amendment of the terms of licences for the online operation of gaming during their term, and the challenge was based on principles of legal certainty and protection of legitimate expectations, which are common to EU law and to the constitutional frameworks of the EU's Member States (in this case, Italy). From that perspective, the Global Starnet Judgment can be particularly relevant for cases involving claims based on the EU Charter of Fundamental Rights and could create a push for a more significant role for the CJEU as a constitutional court for the Union.
There are a few passages of the Global Starnet Judgment that I find particularly interesting:
... a national court which, in a case concerning EU law, considers that a provision of national law is not only contrary to EU law, but also unconstitutional, does not lose the right, or escape the obligation under Article 267 TFEU, to refer questions to the Court of Justice on the interpretation or validity of EU law by reason of the fact that the declaration that a rule of national law is unconstitutional is subject to a mandatory reference to the constitutional court. The effectiveness of EU law would be in jeopardy if the existence of an obligation to refer a matter to a constitutional court could prevent a national court hearing a case governed by EU law exercising the right conferred on it by Article 267 TFEU to refer to the Court questions concerning the interpretation or validity of EU law in order to enable it to decide whether or not a provision of national law was compatible with that EU law ...
... the effectiveness of EU law would be impaired and the effectiveness of Article 267 TFEU diminished if, as a result of there existing a procedure for review of constitutionality, the national court were precluded from referring questions to the Court for a preliminary ruling and immediately applying EU law in a manner consistent with the Court’s decision or case-law ...
Furthermore, although it is true that the procedure laid down in Article 267 TFEU is an instrument for cooperation between the Court of Justice and the national courts, by means of which the former provides the latter with the points of interpretation of EU law necessary in order for them to decide the disputes before them, the fact remains that when there is no judicial remedy under national law against the decision of a court or tribunal of a Member State, that court or tribunal is, in principle, obliged to bring the matter before the Court of Justice under the third paragraph of Article 267 TFEU where a question relating to the interpretation of EU law is raised before it ...
The fact that the [domestic Constitutional Court] gave a ruling on the compatibility of the provisions of national law ... with the provisions of the [national] Constitution which the referring court regarded as constituting, in essence, the same regulatory parameters as [EU law] has no bearing on the obligation, laid down in Article 267 TFEU, to refer questions concerning the interpretation of EU law to the Court of Justice (C-322/16, paras 21 & 23-25, references omitted and emphases added).