Unus pro omnibus, omnes pro uno: The Single Supervisory Mechanism as a Unitary Multilevel Administration

The Single Supervisory Mechanism recoded the institutional law of banking supervision in the European Banking Union (EBU) and brought the European Central Bank (ECB) and National Competent Authorities (NCAs) of participating Member States within a common administrative space. The model underpinning the Mechanism innovatively mixes centralisation and decentralisation features in a polyhedral institutional structure: although the ECB enjoys significant centralised powers to lead banking supervision in the European Banking Union, the principle of subsidiarity is operationalised in a dynamic fashion to enable the NCAs’ decisional power to contribute to the execution ECB’s supervisory tasks. This contribution attempts to recover a sense of unity in the Mechanism, expounding the rationales for its variably decentralised architecture in light of a holistic understanding of the role of NCAs in the pursue of the ECB’s pan-European supervisory mandate. I will conclude that form and function do not go hand in hand in the SSM: despite being formally composed of two layers of administrations, the Mechanism hinges on a centripetal logic to work as a joint administrative apparatus, where banking supervision is executed, according to formal and informal interinstitutional balances of powers, as a shared function of the ECB’s and NCAs’ synergetic action.