The legal framework under which the European Public Prosecutor’s Office (EPPO) is called to operate is particularly complex, given the need for this body to exercise its functions in the legal systems of the Member States, applying both Union and national law. While this may justify the many references to national law contained in the EPPO’s founding Regulation (2017/1939), several among these references present relevant interpretative issues, and may in some cases even have a misleading effect. The article aims at showing examples of these different scenarios. It also touches briefly on the relevance of soft law in the legal framework of the EPPO.

The first of June 2021 marked the start of the operational activities of the European Public Prosecutor’s Office (EPPO). Established by Regulation (EU) 2017/1939 (‘EPPO Regulation’), the EPPO is the European Union body competent to investigate, prosecute and bring to judgment the perpetrators of criminal offences affecting the Union’s financial interests. The EPPO was established by means of enhanced cooperation. At the time of writing, five Member States do not participate in the EPPO: Denmark, Ireland, Poland, Hungary and Sweden. The effective action against crimes affecting the Union budget requires however smooth cooperation between the EPPO and its counterparts not only in the Member States that participate in the enhanced cooperation, but also in the non-participating Member States. This contribution delves into such cooperation and the several issues it raises, first providing for some introductory remarks on the choice of some Member States not to join the enhanced cooperation on the EPPO. It then analyses the two main provisions of the EPPO Regulation concerning the EPPO’s relations with non-participating Member States, Article 99 and, most importantly, Article 105. Finally, this contribution shortly addresses the relevant role played by Eurojust in this context.