Comity

In law, comity is "a practice among different political entities (as countries, states, or courts of different jurisdictions)" involving the "mutual recognition of legislative, executive, and judicial acts."

Comity derives from the Latin comitas, courtesy, from cemis, friendly, courteous.

The doctrine of international comity has been described variously "as a choice-of-law principle, a synonym for private international law, a rule of public international law, a moral obligation, expediency, courtesy, reciprocity, utility, or diplomacy. Authorities disagree as to whether comity is a rule of natural law, custom, treaty, or domestic law. Indeed, there is not even agreement that comity is a rule of law at all." Because the doctrine touches on many different principles, it is regarded as "one of the more confusing doctrines evoked in cases touching upon the interests of foreign states."

The doctrine of international comity was created by a group of Dutch jurists in the late seventeenth century, most prominently Ulrich Huber. Huber and others sought a way to handle conflicts of law in a way that would reinforce the idea of Westphalian sovereignty. Huber wrote that comitas gentium ("civility of nations") required the application of foreign law in certain cases because sovereigns "so act by way of comity that rights acquired within the limits of a government retain their force everywhere so far as they do not cause prejudice to the powers or rights of such government or of their subjects." Huber "believed that comity was a principle of international law" but also that "the decision to apply foreign law itself was left up to the state as an act of free will."

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