Regina (Freedom and Justice Party and Others) v. Secretary of State for Foreign and Commonwealth Affairs and Another

Diplomatic relations — Special missions — Immunity and inviolability from criminal jurisdiction — Customary international law — State agreeing to receive special mission — Whether customary international law requiring that State secure inviolability and immunity from criminal jurisdiction of members of special mission — Nature of immunity — Whether operation of such immunity restricted to official acts Relationship of international law and municipal law — Customary international law — Requirements of customary international law — Incorporation of customary international law into common law — Whether domestic constitutional principles providing bar or impediment to a judge giving effect to customary international law — Whether unresolved uncertainties in scope and field of application of customary rule providing a reason for declining to give effect to the rule at common law Treaties — UN Convention on Special Missions, 1969 — Whether UN Convention on Special Missions representing a codification of customary international law regarding special missions — Extent of core immunities within customary international law — The law of England