The voice recording can be use as evidence in trial as and when permission to lead defence evidence granted by the court. The Section 65 of Indian Evidence Act prescribes the admissibility and the procedure as to how the veracity and the value of evidence are gauged.
The Section 65A and Section 65B under the head of admissibility of the electronics records and as per Section 65 A, which is a special provision in itself, contemplates that the contents of the electronic records may be proved in accordance with the provision of the Section 65B. Further, section 65 B stipulates that any information contained in an electronic records and printed on paper shall be deemed to be a document and admissible in any proceeding without further proof of the original (soft copy) if the conditions are met viz., that computer output was produced by the computer which was regularly used to store information or process information by the person having lawful control over the use, and that further during that period the information was duly fed into the computer in usual course of business and the computer was functioning properly during that period of time.
Affidavit in evidence before Court of the electronic records
A statement before Court on the electronic document retrieved viz., e-mail or other documents retrieved from the computer system, may be admissible in evidence as a document, if the same is in the form of an affidavit and on the followings lines viz., identifying the electronic record containing the statement and describing the manner in which it was produced; further giving such particulars of any device involved in the production of that electronic record as may be appropriate for the purpose of showing that the electronic record was produced by a computer; dealing with any of the matters, to which the conditions mentioned in section 65(2), relate, and purporting to be signed by a person occupying a responsible official position in relation to the operation of the relevant device or the management of the relevant activities (whichever is appropriate) shall be evidence of any matter stated in the certificate; For the purposes of this Sub-section it shall be sufficient for a matter to be stated to the best of the knowledge and belief of the person stating it.
As per the decision the Apex Court in the case of State(NCT of Delhi) v/s Navjot Sandhu@Afsan Guru, Appeal(Cri.) No. 373/2004, held, while examining Section 65 B, that even when an affidavit/certificate under Section 65B is not filed it would not foreclose the Court from examining such evidence provided it complies with the requirements of Section 63 and 65 of the Evidence Act.
So i am sugesting u, file your evidence with affidavit as per mandate of Section 65B of Indian Evidence Act.