(1) In any relevant proceedings a document that is duly authenticated is admissible in evidence.
(2) A document is duly authenticated for the purpose of subsection (1) if it purports to be—
(a) signed or certified by a judge or magistrate of a Commonwealth country making a request;
(b) authenticated by the oath of a witness, or a public officer or a Commonwealth country making a request; or
(c) sealed with an official or public seal of a Minister of State, or a department or public office of the Government, of such a country.
(3) In any relevant proceedings, a certificate purporting to have been given—
(a) by the central authority of a Commonwealth country certifying the matters referred to in—
(i) paragraph (b)(i) or (ii) of the definition of “serious offence” in section 2(1); or
(ii) paragraph (b)(ii) of the definition of “serious offence” in section 2(1); or
(b) by a legally qualified person for the purposes of a request for assistance under section 25 or 27, shall be received as evidence of the matters duly certified by the certificate.
(3) This section does not operate to prevent the proof of any matter, or the admission of any document, in accordance with the regulations or any other law.