The United Nations and International Court of Justice (Immunities and Privileges) Order 1974

17.  Except in so far as in any particular case any privilege or immunity is waived by the Secretary-General, experts (other than officers of the United Nations) performing missions on behalf of the United Nations shall enjoy:—

(a)immunity from suit and legal process in respect of things done or omitted to be done by them in the course of the performance of their missions;

(b)during the period of their missions, including the time spent on journeys in connection with service on such missions, the like immunity from personal arrest or detention and the like inviolability for all papers and documents as is accorded to a diplomatic agent; and

(c)during the period of their missions, including the time spent on journeys in connection with service on such missions, the like exemptions and privileges in respect of their personal baggage as in accordance with Article 36 of the 1961 Convention Articles are accorded to a diplomatic agent.