Legal status of the Holy See

The legal status of the Holy See, both in state practice and according to the writing of modern legal scholars, is that of a full subject of public international law, with rights and duties analogous to those of States.

Although the Holy See, as distinct from the Vatican City State, does not fulfill the long-established criteria in international law of statehood; i.e. having a permanent population, a defined territory, a stable government and the capacity to enter into relations with other states; its possession of full legal personality in international law is evidenced by its diplomatic relations with 180 states, that it is a member-state in various intergovernmental international organizations, and that it is: "respected by the international community of sovereign States and treated as a subject of international law having the capacity to engage in diplomatic relations and to enter into binding agreements with one, several, or many states under international law that are largely geared to establish and preserving peace in the world." As Graham notes:

The fact that the Holy See is a non-territorial institution is no longer regarded as a reason for denying it international personality. The papacy can act in its own name in the international community. It can enter into legally binding conventions known as concordats. In the world of diplomacy the Pope enjoys the rights of active and passive legation. (...) Furthermore, this personality of the Holy See is distinct from the personality of the State of Vatican City. One is a non-territorial institution and the other a state. The papacy as a religious organ is a subject of international law and capable of international rights and duties.

This peculiar character of the Holy See in international law, as a non-territorial entity with a legal personality akin to that of states, has led professor Ian Brownlie to define it as a "sui generis entity".

Moreover, the Holy See itself, while claiming international legal personality, does not claim to be a State. Cardinal Jean-Louis Tauran, former Secretary for Relations with States of the Secretariat of State of the Holy See, has underlined that we must avoid the temptation of assimilating the Holy See and its international action with that of a State, with their thirst for power. For him, the Holy See is unquestionably a sovereign subject of international law but of a predominantly religious nature.

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Wikipedia