In a little more than a decade, the set of public financial rules has reached a significant extension, fueled by the directly proportional relationship between the extent of the financial crises and the interventions of the EU and national regulatory powers. The 2008 global crisis and the crisis related to the Covid-19 pandemic have had relevant impacts on the size of public spending and debt and have triggered the production of financial rules, mainly defined in Europe by the EU. These rules affect the administrative functions and the role of the public administrations. The main objective of the paper is to analyze how the growing increase of public finance law affects the configuration of the administrative systems, by shaping their characteristics on the basis of technical needs. The ultimate goal is to understand whether such a “modeling ability” has resulted in a capacity of improving the administrative system or, on the contrary, has produced negative effects.