The principle of ne bis in idem as an individual right is textually guaranteed in Art. 50 CFR / Art. 54 CISA, on the one hand, and in Art. 4 Prot. No. 7 ECHR, on the other. The CJEU and the ECtHR have delineated many issues in their detailed case law and have reciprocally influenced each other’s jurisprudence. The article identifies three major problems: Firstly, the definition of “criminal proceeding” as a prerequisite for application of the principle relies on the Engel criteria identified by the ECtHR, but it is difficult to incorporate new forms of sanctions, such as “naming and shaming,” into this definition, and the fact that administrative sanctions do not fall within the ambit of ne bis in idem is not justifiably accounted for. Secondly, the courts may have determined which procedural acts meet the requirement of res judicata (terminating a criminal proceeding) and which ones do not. However, it is the Member State itself which determines whether a decision is final and whether national follow-up procedures are permitted, thus reinvigorating the issue of jurisdictional concentration.

The concept of minimum rules is inextricably linked to the approximation of criminal norms in the European Union. In the field of procedural criminal law, the adoption of minimum rules supports the need to facilitate mutual recognition and police and judicial cooperation in criminal matters. This Article seeks to introduce the reader to the world of minimum rules. In order to understand what it means to have minimum rules in a criminal law context, it is necessary to discuss about the origins, the development, the use and the role of minimum rules within this particular context. Following a complete depiction of the way in which minimum rules function in the field of procedural criminal law, the question arises: can Member States go beyond minimum rules?