Primarily there were only 2 types of evidence, i.e. Oral and documentary in The Indian Evidence Act, 1872. In earlier times, it was never comprehended that with the advancement of technology, tape-recorded conversations would eventually play a huge role in providing important evidence in courts. In earlier times there was no provision in the Indian Evidence Act with regards to the admissibility, nature and evidentiary value of an electromagnetic device. However, over the years, the manner of committing crimes has changed drastically. So there is a need to consider Tape recording as evidence.
The earliest case in India, the issue of admissibility of tape-recorded conversation came for consideration in Rupchand v. Mahabir Prasad. In the present case, the court refused to treat tape recording conversation as writing within the meaning of the General Clauses Act, Section 65  but allowed the same to be used under Evidence Act, section 155 . There is no rule of evidence which prevents a party, who is trying to shake the credit of a witness by using the former inconsistent statement, from deposing that while he was involved in the conversation with the witness, a tape recorder was in operation for producing the said tape recorder in support of the assertion that a certain statement was made in his presence was held by the court.
In S. Pratap Singh v. State of Punjab, the tape recorder was considered as evidence. A five judges bench of Apex Court considered the issue and clearly stated that tape-recorded statements are admissible in evidence. They also stated that just because this type of evidence can be easily tampered it cannot be rejected as an evidence on this ground alone. As there are many other documents and pieces of evidence that can be tampered.
In this case, the conversation recorded in the tape recorder was admitted as evidence to corroborate the evidence of witnesses who had stated that such a conversation has taken place.
The Apex Court in Yusufalli Esmail Nagree v. State of Maharashtra considered various aspects of the issue relating to admissibility of tape-recorded conversation. In the present case, the offence was related to section 165-A of the Indian Penal Code. The conversation between the person who wanted to bribe and the complainant was tape-recorded during the investigation. The complainant wanted to use this tape-recorded conversation as evidence against accused but it was argued that the same is violative of section 162 CrPC as well as article 20(3) of the constitution.
In this landmark judgment, the court definitely laid down in unambiguous terms that the process of tape recording offers a precise method of keeping and later reproducing sounds. The Apex Court after examining the entire issue in the light of various pronouncements laid down the following principles:
The contemporaneous dialogue, which was tape-recorded, formed part of res-gestae and is relevant and admissible under section 8 of the Indian Evidence Act.
Under section 7 of the Indian Evidence Act, the contemporaneous tape record of a relevant conversation is a relevant fact and is admissible.
Under section 162 of the Criminal Procedure Code such a statement was not, in fact, a statement made to police during the investigation and, therefore, cannot be held to be inadmissible.
Such a recorded conversation though procured without the knowledge of the accused but the same is not elicited by coercion or compulsion nor extracted by force or against the wishes of the accused. Therefore the protection of article 20(3) was not available.
The magnetic tape-recording can erase and re-use the recording medium. Therefore, the evidence must be received with caution.
The court must be satisfied beyond a reasonable doubt that the record has not been tampered with.
In the case of Ram Singh v. Col. Ram Singh, following essentials were laid down by the Apex Court for admissibility of tape-recorded conversation:
The voice of the speaker must be recognized by the person who has recorded or by others who recognize his voice. Where the maker has refused to recognize the voice it will require very strict proof to determine whether or not it was really the voice of the speaker.
The precision of the tape-recorded statement has to be proved by the person who had recorded the record by satisfactory evidence direct or circumstantial.
Every possibility of tampering with or erasure of a part of a tape-recorded statement must be ruled out otherwise it may render the said statement out of context and, therefore, inadmissible.
According to the rules of Evidence Act, the statement must be relevant.
The recorded cassette must be carefully sealed and kept in safe or official custody.
The voice of the speaker should be clearly audible and not lost or distorted by other sounds or disturbance .
Subsequently, the Information Technology Act, 2000, (w.e.f. 17.10.2000) came into force hence, the traditional concept of evidence stands totally reformed. Section 2(r) of this Act is relevant in this respect which defines information in electronic form as, “information generated, sent, received or stored in media, magnetic, optical, computer memory, microfilm, computer-generated micro fiche or similar device”. Under section 2 (t) ‘electronic record’ means data, record or data generated, image or sound stored, received or sent in an electronic form or microfilm or computer-generated micro fiche.
In the case of N. Sri Rama Reddy v. V.V. Giri. There was an issue raised that if such evidence is primary and direct or not? The court held that like any document the tape record is considered as primary and direct evidence admissible of what has been said and picked up by the receiver.
The Supreme Court in the case of Ziyauddin Burhanuddin Bukhari v. Brijmohan Ramdas Mehta , submitted that the use of tape-recorded conversation was not only for the purpose of corroboration and contradiction but can be used as satisfactory evidence of what was found recorded and if not tampered, it could be a subject to the provisions of the Evidence Act and used as a piece of substantive evidence. If there is any doubt related to the recording then its authenticity is to be duly established.
With the present world and with the growth of technology, tape-recorded conversations as pieces of evidence have emerged as one of the positive and effective changes that have taken place in legislation. Considering the crimes of today’s world it is necessary to remain well-informed with the latest technologies available and all efforts need to be made to admit evidence which is relevant and which may have been obtained by the use of such technology. There is no ambiguity regarding the chances of tampering with such forms of evidence. However, their importance and relevance cannot be overlooked. It is evident that the judiciary has made immense efforts in order to provide proper guidelines with respect to the admissibility of tape-recordings as well as other electronic records.
Impeaching credit of witness: The credit of a witness may be impeached in the following ways by the adverse party, or with the consent of the Court, by the party who calls him:—(1) By the evidence of persons who testify that they, from their knowledge of the witness, believe him to be unworthy of credit; (2) By proof that the witness has been bribed, or has accepted the offer of a bribe, or has received any other corrupt inducement to give his evidence; (3) By proof of former statements inconsistent with any part of his evidence which is liable to be contradicted; Explanation: A witness declaring another witness to be unworthy of credit may not, upon his examination-in-chief, give reasons for his belief, but he may be asked his reasons in cross-examination, and the answers which he gives cannot be contradicted, though, if they are false, he may afterwards be charged with giving false evidence
 Section 165A in The Indian Penal Code: Rep. by the Prevention of Corruption Act, 1988 (49 of 1988), sec. 31.]
 162. Statements to police not to be signed: Use of statements in evidence.
(1) No statement made by any person to a police officer in the course of an investigation under this Chapter, shall, if reduced to writing, be signed by the person making it; nor shall any such statement or any record thereof, whether in a police diary or otherwise, or any part of such statement or record, be used for any purpose, save as hereinafter
provided, at any inquiry or trial in respect of any offence under investigation at the time when such statement was made: Provided that when any witness is called for the prosecution in such inquiry or trial whose statement has been reduced into writing as aforesaid, any part of his statement, if duly proved, may be used by the accused, and with the permission of the Court, by the prosecution, to contradict such witness in the manner provided by section 145 of the Indian Evidence Act, 1872 (1 of 1872 ); and when any part of such statement is so used, any part thereof may also be used in the re-examination of such witness, but for the purpose only of explaining any matter referred to in his cross-examination.
(2) Nothing in this section shall be deemed to apply to any statement falling within the provisions of clause (1) of section 32 of the Indian Evidence Act, 1872 (1 of 1872 ), or to affect the provisions of section 27 of that Act. Explanation.- An omission to state a fact or circumstance in the statement referred to in subsection (1) may amount to contradiction if the same appears to be significant and otherwise relevant having regard to the context in which such omission occurs and whether any omission amounts to a contradiction in the particular context shall be a question of fact.
 (3) No person accused of any offence shall be compelled to be a witness against himself
 7. Facts which are the occasion, cause or effect of facts in issue.—Facts which are the occasion, cause, or effect, immediate or otherwise, of relevant facts, or facts in issue, or which constitute the state of things under which they happened, or which afforded an opportunity for their occurrence or transaction, are relevant. Illustrations (a) The question is, whether A robbed B. The facts that, shortly before the robbery, B went to a fair with money in his possession, and that he showed it, or mentioned the fact that he had it, to third persons, are relevant. (b) The question is, whether A murdered B. Marks on the ground, produced by a struggle at or near the place where the murder was committed, are relevant facts. (c) The question is, whether A poisoned B. The state of B’s health before the symptoms ascribed to poison, and habits of B, known to A, which afforded an opportunity for the administration of poison, are relevant facts.