Article 15
Except in so far as in any particular case any privilege or immunity is waived by the Secretary-General of the Group, an expert (other than an officer of the Group) serving on any committee of the Group or employed on missions on its behalf shall, so far as is necessary for the carrying out of his functions, including during journeys made in carrying out his functions and in the course of such missions, enjoy:—
immunity from suit and legal process in respect of things done or omitted to be done by him in the exercise of his functions, except in the case of a motor traffic offence committed by him or in the case of damage caused by a motor vehicle belonging to or driven by him;
while he is employed by the Group, the like inviolability for all his official papers and documents as is accorded to a diplomatic agent.