(1) A trustee who has authorised the receipt of profits arising from trust property by or by the agent of the person entitled to such profits shall not, if -
(a) that person or agent actually received the profits under that authority, and
(b) the trustee makes a return as required by section 890 of the name, address and profits of that person,
be required to do any other act for the purpose of the assessment of that person, unless the Revenue Commissioners require the testimony of the trustee pursuant to the Income Tax Acts.
(2) An agent or receiver of any person resident in the State, other than an incapacitated person, shall not, if that agent or receiver makes a return as required by section 890 of the name, address and profits of that person, be required to do any other act for the purpose of the assessment of that person, unless the Revenue Commissioners require the testimony of the agent or receiver pursuant to the Income Tax Acts.