Introduction

The implementation of EU law is primarily the responsibility of the Member States. Through soft law instruments, such as working documents and interpretative communications, the European Commission aims to provide guidance to the Member States in the application, transposition , interpretation and enforcement (in short: the implementation) of EU hard law.

Commission soft law is not legally binding and has a highly ‘informal’ character. Soft law documents are not adopted according to a Treatybased legislative procedure. The European Parliament and the Council have not been attributed a formal role in the adoption process, nor have the Member States.

Despite the fact that soft law documents are not legally binding, soft law may influence the way in which EU law is implemented in the national legal order by national authorities. In other words, soft law may have a steering effect on national administrative authorities. Soft law is assumed to provide legal certainty and transparency to national authorities charged with the implementation of EU law. The steering pressures of soft law are likely to be constructed by (the threat of) the Commission opening an infringement procedure or by imposing financial sanctions. Furthermore, steering pressures on national authorities might be constructed by national courts using EU administrative soft law as an aid to interpretation.

The (intended) steering character of soft law contrasts with the absence of legal bindingness and the informality of the adoption process. As a result, several questions arise that relate to the concept of the separation of powers . Does governance through soft law result in too much executive power concentrated in the hands of the European Commission ? Does the informal adoption process of soft law imply that sufficient checks and balances are absent? And does the involveement of the Commission in the implementation process render indiscernible the division of powers between the Commission and the Member States?

In his book ‘The Three Branches: A Comparative Model of Separation of Powers (2013)’ Möllers develops a theoretical model on the separation of powers . Möller's theory builds on the idea that acts of public authority are justified, and thus legitimised, because they institutionalise - through the processes of legislative, judicial and executive lawmaking – democratic self-determination and individual self-determination.