Universality of interface norms under constitutional pluralism : an analysis of Ireland, the EU and the ECHR

Abstract

The theory of constitutional pluralism suggests that interacting legal orders that are (or claim to be) constitutional in nature need not—and should not—necessarily be regarded as being hierarchically arranged, with one ‘on top of’ the others. Rather, the relationships between the orders can be conceived of heterarchically. However, there is an assumption in much of the literature that the ‘interface norms’ that regulate the relationships within such a heterarchy are universal by nature, capable of undifferentiated application across differing constitutional orders. This thesis examines whether interface norms are in fact universal by nature, or whether they are relationship- and context-dependent, taking as its field of study three interacting legal orders—those of Ireland, the European Union, and the European Convention on Human Rights. It uses an established model of constitutional pluralism based on ‘coordinate constitutionalism’ to test the assumption of universality across three constitutional frames: the ‘vertical’ relationship between Ireland and the European orders, the ‘horizontal’ relationship between the European orders, and the ‘triangular’ panoply of state, Union and Convention. Having analysed the interface norms at work in these relationships, both in isolation and in the round, the thesis concludes that these norms are not in fact universal, and that different conceptions of constitutional pluralism need to pay much greater attention to the specific nature of any given constitutional order and its relationship with other orders in the constitutional heterarchy.