Sincere Cooperation and Respect for National Identities
Article 4 of the Treaty on the European Union is a core provision to understand the ‘federal’ nature of the European Union. It is composed of three paragraphs, any of which tries to strike a balance between the constitutive units of the composite legal order, namely the EU, on the one hand, and the Member States, on the other. The first paragraph enshrines the so-called ‘principle of presumed Member States competences’, according to which competences not conferred upon the EU remain to the Member States. The second paragraph requires the EU to respect Member States’ national identities, inherent in their fundamental political and constitutional structures. The third paragraph enshrines the principle of sincere cooperation. In this respect, all the paragraphs express a sort of ‘federal concern’. Article 4(1) TEU is devoted to the vertical division of competences and strengthens the respect of the principle of conferral, Article 4(2) TEU is devoted to the identities of the Member States of the EU thus protecting diversities in the composite legal order, and Article 4(3) TEU is devoted to loyalty, which, like in many federal or compound legal orders, should inform the cooperation among levels of government.