State immunity — Jurisdictional immunity — Employment dispute — Claim brought by State radio announcer — Entitlement to immunity where employment in pursuit of public purposes of foreign State and tasks not purely mechanical — Distinction between interpreter and announcer

States Holy See — Vatican City — Status under international law — Lateran Treaty, 1929 — Extent of entitlement to immunity from jurisdiction — Employment dispute — Claim brought by Vatican City radio announcer — Recognition of special requirements of Church's “mission in the world” — The law of Italy