Article 19
Except in so far as in any particular case any privilege or immunity is waived by the Presidency and subject to the production of the required document, witnesses, to the extent necessary for their appearance before the Court for the purposes of giving evidence (including the time spent on journeys in that connection), shall enjoy:–
the like immunity from personal arrest or detention as is accorded to a diplomatic agent;
immunity from suit and legal process (even after their appearance and testimony before the Court) in respect of acts, including words spoken or written, performed by them in the course of their appearance and testimony before the Court;
the like inviolability for all papers, documents and materials relating to their appearance and testimony before the Court as is accorded to a diplomatic agent;
immunity from seizure of personal baggage unless there are serious grounds for believing that the baggage contains articles the import or export of which is prohibited by the law or controlled by quarantine regulations in the United Kingdom.
For the purposes of this Article, the “required document” means a document provided by the Court certifying that appearance before the Court by the witness is required by the Court, and specifying a time period during which such appearance is necessary.
Sub-paragraph (d) of paragraph (1) shall not apply to any person who is a British citizen, a British overseas territories citizen, a British Overseas citizen, a British National (Overseas) or permanently resident in the United Kingdom.