State immunity — Jurisdictional immunity — Foreign States — Institutes of foreign States — Vatican City Institute for Religious Works — Scope of entitlement of Institute and its officials to jurisdictional immunity — Attachment and execution — Bank accounts — Seizure of documents relating to accounts — Criteria for determining which assets immune from execution — Immunity of assets allegedly used for performance of sovereign functions — Whether specific allocation of funds for sovereign tasks required

States — Holy See — Vatican City — Entitlement of Holy See to sovereign immunity

States — Sovereignty and independence — In foreign relations — Request for mutual assistance by foreign State — Request for seizure of documents relating to bank deposits of Vatican City Institute — Whether immunity from execution prevents seizure of documents — The law of Switzerland