Regina (HRH Sultan of Pahang) v Secretary of State for the Home Department  EWCA Civ 616;  WLR (D) 183
“The question of who was a head of state such as to attract state immunity was a matter for the Secretary of State for Foreign and Commonwealth Affairs and not for the court. A certificate issued by the Secretary of State under section 21 of the State Immunity Act 1978 was conclusive evidence of the status of a territory for the purposes of Part I of the 1978 Act. The certificate was the only proper means by which the court could, for the purposes of the common law where it continued to apply, inform itself of a territory’s status and of the identity of the head of state.”
WLR Daily, 25th May 2011
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