Although the significance of the ne bis in idem principle is undisputed, it has proven difficult to apply it consistently over the years. In the EU, the Court of Justice (CJEU) case law has long diverged according to the field of law. Notably, since Aalborg Portland and Toshiba an antitrust-specific threefold condition of idem (same person, same facts, same protected legal interest) has been developed, which was at odds with the twofold identity approach (same offender and same facts) established in Van Esbroek and applied to other areas of law, as confirmed in Menci. Against this background, in two recent seminal judgements (bpost and Nordzucker) the Grand Chamber has finally levelled the legal playing field, ruling in favour of a unified test shaped on Menci. Although the overruling is welcome, it needs to be accompanied by a careful elaboration on the conditions legitimating limits to the ne bis in idem principle.
Cappai, M., Colangelo, G. (2023). The long road to a unified test for the European ne bis in idem principle. EUROPEAN PUBLIC LAW, 28(4/2022), 487-514.