The EU has developed formal and informal political mechanisms to address serious violations of human rights by Member States. Yet, the bulk of the protection of human rights in the EU remains largely in the hands of courts, at both national and EU level. The coming into force of the EU Charter of Fundamental Rights has reinforced the EU commitment to respect for fundamental rights, and the legitimacy of EU institutions in holding Member States accountable for human rights violations. The Charter, however, only applies to Member States when they implement EU law. This restriction limits the centralizing and federalizing potential of the Charter, but the manner in which the EU and national institutional actors in charge of ensuring the protection of individuals’ rights, notably the Commission, the CJEU and national courts, invoke the Charter and define its scope, varies. This variation determines the actual degree of EU control over Member States’ activities that interfere with fundamental rights. Existing literature has stressed the role of courts in the development of EU human rights law and integration. Yet, courts are largely reactive institutions, which respond to disputes brought to them, even if they can also encourage certain types of claims or claimants. This paper examines the dynamics of Charter-based litigation at both national and EU level, through the lenses of a ‘legal opportunities’ approach, focusing on post-2010 Hungary and France. These two countries offer good case-studies to test a ‘legal opportunities’ explanation of Charter-driven federalization, as they represent, respectively, cases of closure and opening of domestic legal opportunities for the judicial protection of fundamental rights, which coincide with the coming into force of the Charter. It suggests that the weakening of domestic opportunities for human rights litigation can have a strong federalizing effect, if certain conditions are fulfilled.
