It has been 20 years since Union citizenship was introduced under the Treaty of Maastricht, yet it remains a topical and contemporary issue. The main research question underlying this study is whether and how European citizenship affects the constitutionalisation of the European Union.
The present study connects European citizenship with European constitutional processes, in order to grasp the constitutional relevance of EU citizenship. To this end, the different aspects of European citizenship are specifically linked to features that are, commonly, found in constitutions. The effect of and relation between European citizenship and four of these constitutional ‘building blocks’ are assessed.
First of all, the effect of European citizenship to the vertical division of powers between the Member States and the European Union is analysed. Second, the way European citizenship relates to a common ideology, existing of fundamental rights protection and democracy, is discussed. Moreover, the effect of European citizenship on judicial review and the hierarchy of norms in the European Union is addressed.
Finally the question is posed how and to what extend European citizenship affects the constitutionalisation of the European Union and how European citizenship can be placed within the European constitutional context.