The grant and revocation of passports is an exercise of prerogative power. A passport was defined in R v Brailsford [1905] 2 KB 730 by Lord Alvestone CJ as:

'[A] document issued in the name of the Sovereign on the responsibility of a Minister of the Crown to a named individual, intended to be presented to the Governments of foreign nations and to be used for that individual's protection as a British subject in foreign countries.'

As regards judicial review of a decision to refuse to issue a passport, see R v Secretary of State for Foreign and Commonwealth Affairs, ex parte Everett [1989] 1 All ER 655.