Subject to rules of court, where in any civil proceedings a statement made by a person who is not called as a witness in those proceedings is given in evidence by virtue of section 2 of this Act—
(a) any evidence which, if that person had been so called, would be admissible for the purpose of destroying or supporting his credibility as a witness shall be admissible for that purpose in those proceedings; and
(b) evidence tending to prove that, whether before or after he made that statement, that person made (whether orally or in a document or otherwise) another statement inconsistent therewith shall be admissible for the purpose of showing that that person has contradicted himself:Provided that nothing in this subsection shall enable evidence to be given of any matter of which, if the person in question had been called as a witness and had denied that matter in cross-examination, evidence could not have been adduced by the cross-examining party.
Subsection (1) above shall apply in relation to a statement given in evidence by virtue of section 4 of this Act as it applies in relation to a statement given in evidence by virtue of section 2 of this Act, except that references to the person who made the statement and to his making the statement shall be construed respectively as references to the person who originally supplied the information from which the record containing the statement was compiled and to his supplying that information.
Section 3(1) of this Act shall apply to any statement proved by virtue of subsection (1)(b) above as it applies to a previous inconsistent or contradictory statement made by a person called as a witness which is proved as mentioned in paragraph (a) of the said section 3(1).