Jus de non evocando

The Jus de non evocando is an ancient feudal right, stating that no one can be kept from the competent court. It derives from a medieval principle that subjects of the Crown were entitled to ius de non evocando, the right to enjoy the jurisdiction and protection of the Crown to which they were loyal. As such it is still present in several constitutions, such as the German constitution, the Italian constitution and the Dutch constitution.

It has today become an important concept in public international law by which states refuse to extradite their own citizens. Some countries may refuse to extradite non-nationals, who, because of their crimes, may be subject to the death penalty. This may be seen in the case of Canada and Mexico vis-à-vis the United States.

This principle is frequently argued in cases of the International Criminal Tribunal for Rwanda (ICTR) and former Yugoslavia (ICTY). The foundation lies in that the international tribunal, by seizing jurisdiction over an international criminal trial from national courts, is violating the principle of jus de non evocando. The Trial Chamber in the case of Dusko Tadic (IT-94-1 of the ICTY) stated that states give up some measure of sovereignty to be a part of the UN and the ICTY is a product of the UN, therefore there is no violation.

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