This Part examines the immunity of the State as compared to immunities enjoyed by other persons, legal or natural, either as part of the State or as connected with the State or, as in the case of international organizations, separate from State. References have previously been made to the place of individuals in the definition of the State in Chapter 10.
When it comes to the immunity of individuals acting on behalf of the State (Chapter 18), the critical determinant of the nature and scope of immunity is a person’s proximity to the State; the closer a person is to the centre of the State, the higher their immunity tends to be. Thus, heads of State, heads of government and the Minister for Foreign Affairs (and possibly other senior ministers of the central government) enjoy immunity ratione personae, which is conferred by reason of status as key representatives of the State. This immunity is also enjoyed pursuant to international convention and under international custom by the head and members of the diplomatic staff of a diplomatic mission; and, by the 1969 Convention on Special Missions and other arrangements, by members of special missions, members of permanent missions to international organizations, and by delegates to international conferences of international organizations. This personal immunity, being afforded by reason of the office, ceases when the official vacates the post. Immunity ratione materiae, on the other hand, affords immunity to authorized representatives of the State when they perform an act of State. It applies to officials, functionaries, and employees of States, whether serving or out of office, to afford them immunity in respect of acts which are performed in an official capacity.
Chapter 19 considers immunities that have their own special features, which have been codified in bilateral or multilateral agreements other than the UNCSI. It considers the scope of immunities granted to international organizations and their basis in specific agreements. International organizations may enjoy legal personality and be granted privileges and immunities that resemble but differ from those granted to the State. Chapter 14 in the previous Part covers the practice of international organizations as regards the employment exception to immunity.
Chapter 19 also examines immunities subject to ‘special regimes’ in international law. These include diplomats and the diplomatic mission and consular relations, which are governed by the 1961 and 1964 Vienna Conventions. Another special regime is that which applies to visiting armed forces. The law of armed conflict regulates the conduct of a State’s armed forces, but the particular situation where the armed forces of one State visit the territory of another State with its consent requires the regulation of their status, privileges, and immunities while in the territory of the receiving State. Bilateral or multilateral conventions dealing with the status of forces govern these matters (see also Chapter 9 for a discussion in the context of ECSI and UNCSI and Chapter 15 on the territorial tort exception). The rules applicable to policing and law enforcement personnel present in another State’s territory are also briefly addressed.