Learning from failure in ‘an Integral Part’ of EU Law: interpretation of international treaties in the CJEU

Abstract The Court of Justice of the European Union has been criticised increasingly for its approach to international law. While much literature focuses on reluctance to apply international law (ie refusing direct effect), this criticism also includes interpretation, arguably a more contentious area. The Court interprets international treaties through either the Vienna Convention or its own teleological method, with the latter increasingly applied. The legitimacy of applying localised methods of interpretation to international treaty law is debated in scholarship. Whether the Court’s case law applying international law is Völkerrechtsfreundlichkeit (friendliness to international law) is the focus of most contributions in this area. This Article seeks to move beyond that debate by demonstrating the Court should in all instances seek to achieve the legal imperatives of certainty and justice. It is explained that justice divides into ‘thin’ and ‘thick’ forms. Whilst ‘thin’ justice is widely accepted and amounts to treating like cases alike, substantive (‘thick’ justice) outcomes are inherently debatable. The Article proves the Court is failing to clearly distinguish cases (‘thin’ justice) and that case law is uncertain. There are also significant questions concerning ‘thick’ justice. The Court has been subject to criticism for substantive outcomes in this area, with the Commission and Council even seeking to limit its role. With case law that is uncertain and appears unjust it is argued that there is failure in this ‘integral part of EU law.’ The Court is now under increased pressure, and it is uncertain how it will respond. There are certainly cautionary lessons to be learned concerning the importance of paying proper attention to justice and certainty for EU law as a whole, and beyond.