The past, present and future of the ne bis in idem dialogue between the Court of Justice of the European Union and the European Court of Human Rights: the cases of Menci, Garlsson and Di Puma

The cases of Menci (C-524/15), Garlsson (C-537/16) and Di Puma (C-596/16 and C-597/16) deal with the duplication of criminal and punitive administrative proceedings for the same conduct in the area of VAT and market abuse. The Court of Justice of the European Union (CJEU) held that this duplication of proceedings constitutes a limitation of the ne bis in idem principle of Article 50 of the Charter of Fundamental Rights (Charter). This infringement is only justified if the requirements of the limitation clause of Article 52(1) of the Charter are met. The judgments were highly anticipated as they constitute the response of the CJEU to the judgment in A and B v Norway delivered by the European Court of Human Rights (ECtHR), in which the ECtHR lowered the level of protection afforded by the ne bis in idem principle of Article 4 of Protocol No. 7 to the European Convention of Human Rights (A4P7 ECHR). While there are differences between the approaches taken by both courts, it appears that the reasoning of the CJEU in the judgments largely mirrors that of the ECtHR in A and B v Norway. This article frames the judgments in terms of the dialogue between the CJEU and ECtHR on the ne bis in idem principle. It does so chronologically, by focusing on the past, present and future of the ne bis in idem dialogue between both European courts.