Parliament (Privileges, Immunities and Powers) Act 1962 s 9

s 9 Exemption from certain duties

9.—(1) It shall not be lawful —(a) to require any Member or officer of Parliament to serve as an assessor on any tribunal; or (b) while in attendance on Parliament or any committee, to compel such person to attend as a witness in any court or tribunal or at any commission of inquiry or committee of inquiry or before any like authority empowered to summon witnesses.[43/2007] (2) The production of a certificate signed by the Speaker or the chairman of the committee shall be deemed sufficient proof of attendance on Parliament or the committee.