The Import of International Customary Law into the EU Legal Order: The Adequacy of a Direct Effect Analysis

The EU case law, embodied by the Racke judgment, constituted a normative compromise between the judicial treatment of international customary law and that of international treaties. Indeed, the lack of precision of an international customary norm would not prevent it from being assessed by the EU Courts on the merits of the case, albeit to a lesser degree of judicial review. The lack of precision of an international treaty provision would in contrast make it unenforceable on the facts of the case (subject to two exceptions and the doctrine of consistent interpretation), whereas when sufficiently precise, the treaty provision would be assessed in full by the EU Courts. In Air Transport Association of America, the Court of Justice projected onto the challenged EU secondary act a hybrid and alternative direct effect analysis, borrowed in part from the classical approach to direct effect and in part from the first branch of the direct concern standing requirement whilst also adopting an absolute manifest violation test due to an imprecision bias targeted at all international customary norms. The Court of Justice thereby disrupted this normative compromise: any international customary norm, provided that it or the challenged EU secondary act passes the hybrid direct effect test, would also trigger a marginal form of judicial review in validity review actions before the EU Courts, regardless of its nature and inherent qualities. This chapter aims to argue that the direct effect requirements, which emerge from the case law on the import of international treaties into the EU legal order, remain adequate to assess the judicial enforceability of ordinary international customary law in the EU legal system minus the requirement revolving around the broad logic and nature of the international customary norm. International customary norms should, accordingly, be assessed on the basis of the same direct effect criteria as those applicable to the Constitutive Treaties and EU secondary acts when assessing their relation to Member States’ national legal orders. However, the precision and unconditionality criteria ought to be appreciated with more flexibility with regard to the import of international customary norms in order to account for their unique normative character. The ‘express reference’ ‘implementation’ exceptions specific to the international treaty judicial context may also be transposed to the assessment of international customary law in validity review actions. The application of the doctrine of consistent interpretation to international customary norms and their use as interpretative tools before the EU Courts constitute judicial implications of the principle of primacy of international customary law binding upon the Union over inconsistent EU secondary acts.