17 Colum. J. Eur. L. 231 (2010)
Aurdlian Portuese, University of Paris II Panthéon-Assas.
The principle of subsidiarity-whereby a power shared between the European Union and its Member States is exercised at the lowest appropriate level of governance-is a general principle of European Union law the justiciability of which has been widely discussed. The justiciability of the subsidiarity principle has been criticized for underlining its political relevance. However, this critique lacks the power to explain both the weight of the principle of subsidiarity in the E. U. Treaties and the case law regarding the subsidiarity principle. What is the principle of subsidiarity and what degree of justiciability does it have?