CYIL Vol. 7, 2016

PAVEL CABAN CYIL 7 ȍ2016Ȏ On the other hand, the former proposition would mean that the treaty based immunity ratione materiae is implicitly limited by the exception(s) to general customary immunity ratione materiae (which are discussed in more detail below). Arguments in favour of this proposition of one and single regime of immunity ratione materiae might be as follows: The differentiation between immunity ratione materiae contained in treaties (and analogous customary norms), on the one hand, and immunity ratione materiae of all other state officials defined in customary international law, on the other hand, is based only on the fact of different places of business. The treaty-based immunity ratione materiae protects the exercise of official conduct of a small circle of state officials performing their functions abroad, in the territory of a foreign state. These officials are directly “exposed” to the jurisdiction of foreign states, which lead states to expressly regulate their immunity ratione materiae in relevant treaties. On the other hand, the vast majority of state officials, protected by general customary immunity ratione materiae , perform their official functions in their home state, and, therefore, their official acts, covered by the immunity, will, in most cases, have no relevant connection with the jurisdiction of any foreign state. Therefore no explicit regulation of their immunity ratione materiae in treaties was regarded as necessary. However, the fact that immunity ratione materiae of one specific sector of state officials is expressly reflected in treaties does not seem to justify any substantive differentiation between this treaty based immunity ratione materiae and customary immunity ratione materiae of all other state officials. What would be further consequences of this concept? Immunity ratione materiae protects all state officials in respect of their official acts during and after their term of office with erga omnes effect. The same applies with regard to state officials performing their functions abroad (diplomats etc.), who are additionally, during their term of office abroad, protected by immunity ratione personae . Their immunity ratione materiae , applicable during and after their term of office, has also erga omnes effect; however, this effect is mostly only theoretical, since they perform their functions in (and have to be protected primarily against) the jurisdiction of one concrete, receiving state (this fact is reflected in relevant provisions of treaties mentioned above). And it also means that any existing exceptions to immunity ratione materiae, examined below , should limit also immunity ratione materiae defined in relevant treaties. If treaty-based immunity ratione materiae would be a different “species” and would not be limited by the same exceptions as general immunity ratione materiae of all state officials, 12 it would create a paradoxical situation when a crime which is subject to an exception to general customary immunity ratione materiae (namely exception for officials: he or she is entitled to the general immunity ratione materiae of state officials which derives from state immunity. Therefore, when in a third state, a former diplomat is not entitled to immunity ratione materiae with respect to prosecution for international crimes.”; ibid . pp. 850-851). 12 For possible application of so called “territorial exception” to immunity in respect of treaty-based immunity ratione materiae see further below.

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