The multilevel governance of emergency in counterterrorism.The “globalization” of the law of exception?

In exceptional circumstances, defined as “emergencies”, states can limit human rights and personal freedoms, as long as restrictions are proportionate and necessary. From a comparative constitutional law perspective, several “emergency models” can be envisaged. At the same time, several international law tools provide for the possibility to derogate guarantees embodied therein in order to tackle exceptional circumstances. Since September 11, 2001, international terrorism has represented one of the biggest challenges for democratic countries and such a “global” threat still afflicts our democracies. Nevertheless, few countries have triggered their emergency provisions, as contained either in national constitution or legislation. Rather, limitations of human rights are often embodied in “ordinary” measures, so posing a high risk of “normalizing” restrictions of rights outside of a legally regulated and temporary state of emergency. How far has the “normalization” of exceptional circumstances come in times of international terrorism in democratic systems? Which is the relationship between international law provisions allowing derogation from human rights embodied in treaties and national emergency provisions? How can the international level impact on the other levels in determining exceptional measures? Are several de facto emergency provisions challenging the above-described models, which classify emergency regimes from a constitutional law perspective?