This article provides a normative framework for evaluating the moral permissibility of various defences of European Union (EU) values against their violation in EU member states. This requires, first, a coherent interpretation of EU values as the values of liberal democracy; second, a clear notion of when they are violated; third, a theory of how liberal democracy can be defended with measures that are consistent with the values of liberal democracy themselves; and, finally, a discussion of what the EU’s role is in this defence. The article argues that it would be permissible for the EU to combine a number of political, cultural, socio-economic and legal responses in a concentric defence of liberal democracy as long as they respect the separation of powers doctrine and do not rely on problematic notions of collective responsibility.