Fundamental Rights as Constraints to and Triggers for Differentiated Integration

Abstract

When looking for possible constraints on Differentiated Integration, the fundamental values of the European Union (EU) seem an obvious starting point. Both the Charter of Fundamental Rights and the values articulated in Art. 2 TEU are cross-cutting across EU states. However, while fundamental values have acted as centralising devices in other federal settings, in an EU context marked by extensive value disagreement, they may also act as pathways for differentiation. Insofar as national constitutional orders disagree on the scope of EU rights, attempts to ground EU law in fundamental values trigger inevitable interpretive conflicts across states. This paper will use the examples of asylum and the European Arrest Warrant to demonstrate this argument: while EU law may use fundamental values as a reason to harmonise EU law across states, such values may also be invoked to question the principle of mutual trust underlying the EU legal order, thereby causing rather than limiting differentiation.