Die Ultra-vires-Kontrolle als Institut des Unionsrechts

<jats:p>Who ultimately decides where the European Unions competences end? Benedikt Riedls analysis of the constitutional foundations in the member states and the EU treaties shows that ultra vires review is part of EU law, revealing it to be a shared European responsibility, with national constitutional courts and the European Court of Justice each playing distinct but complementary roles within a coherent legal framework.</jats:p>