Explain the theories of immunity and the functional-necessity doctrine.

Relations, 1961) Mission-level: inviolability of premises (Art. 22), archives (Art. 24), the diplomatic bag (Art. 27), premises' tax exemption (Arts. 23, 28). Agent-level: personal inviolability (Art. 29); total criminal immunity with three civil exceptions (Art. 31 — real-property actions, succession, professional/ commercial activity); tax and customs exemptions (Arts. 34–36); extension to families and graded staff (Art. 37); duration until departure, with official-act immunity enduring (Art. 39); waiver by the sending state alone (Art. 32); duties to respect local law and non-interference (Arts. 41– 42); persona non grata as the receiving state's ultimate answer (Art. 9). The PIL focus: immunity's rationale (function, not dignity); the gradations (family/diplomatic/ administrative staff); and the pair's meaning — immunity = no jurisdiction; inviolability = no coercion at all.