Quality of Evidence to Prove or Disprove a Fact

“In view of these considerations, we have no hesitation in holding that the contention that in a murder case, the court should insist upon plurality of witnesses, is much too broadly stated. Section 134 of the Indian Evidence Act has categorically laid it down that “no particular number of witnesses shall in any case, be required for the proof of any fact”. The legislature determined, as long ago as 1872, presumably after due consideration of the pros and cons, that it shall not be necessary for proof or disproof of a fact to call any particular number of witnesses. In England, both before and after the passing of the Indian Evidence Act, 1872, there have been a number of statutes as set out in Sarkar’s Law of Evidence — 9th Edn., at pp. 1100 and 1101, forbidding convictions on the testimony of a single witness. The Indian Legislature has not insisted on laying down any such exceptions to the general rule recognized in s.134 quoted above. The section enshrines the well-recognized maxim that “Evidence has to be weighed and not counted”. Our Legislature has given statutory recognition to the fact that administration of justice may be hampered if a particular number of witnesses were to be insisted upon. It is not seldom that a crime has been committed in the presence of only one witness, leaving aside those cases which are not of uncommon occurrence, where determination of guilt depends entirely on circumstantial evidence. If the Legislature were to insist upon plurality of witnesses, cases where the testimony of a single witness only could be available in proof of the crime, would go unpunished. It is here that the discretion of the presiding judge comes into play. The matter thus must depend upon the circumstances of each case and the quality of the evidence of the single witness whose testimony has to be either accepted or rejected. If such a testimony is found by the court to be entirely reliable, there is no legal impediment to the conviction of the accused person on such proof. Even as the guilt of an accused person may be proved by the testimony of a single witness, the innocence of an accused person may be established on the testimony of a single witness, even though a considerable number of witnesses may be forthcoming to testify to the truth of the case for the prosecution. Hence, in our opinion, it is a sound and well-established rule of law that the court is concerned with the quality and not with the quantity of the evidence necessary for proving or disproving a fact. Generally speaking, oral testimony in this context may be classified into three categories, namely:
(1) Wholly reliable.
(2) Wholly unreliable.
(3) Neither wholly reliable nor wholly unreliable.

In the first category of proof, the court should have no difficulty in coming to its conclusion either way — it may convict or may acquit on the testimony of a single witness, if it is found to be above reproach or suspicion of interestedness, incompetence or subornation. In the second category, the court, equally has no difficulty in coming to its conclusion. It is in the third category of cases, that the court has to be circumspect and has to look for corroboration in material particulars by reliable testimony, direct or circumstantial. There is another danger in insisting on plurality of witnesses. Irrespective of the quality of the oral evidence of a single witness, if courts were to insist on plurality of witnesses in proof of any fact, they will be indirectly encouraging subornation of witnesses. Situations may arise and do arise where only a single person is available to give evidence in support of a disputed fact. The court naturally has to weigh carefully such a testimony and if it is satisfied that the evidence is reliable and free from all taints which tend to render oral testimony open to suspicion, it becomes its duty to act upon such testimony. The law reports contain many precedents where the court had to depend and act upon the testimony of a single witness in support of the prosecution. There are exceptions to this rule, for example, in cases of sexual offences or of the testimony of an approver; both these are cases in which the oral testimony is, by its very nature, suspect, being that of a participator in crime. But, where there are no such exceptional reasons operating, it becomes the duty of the court to convict, if it is satisfied that the testimony of a single witness is entirely reliable. We have, therefore, no reasons to refuse to act upon the testimony of the first witness, which is the only reliable evidence in support of the prosecution.”

Supreme Court
Vadivelu Thevar v. State of Madras, 1957 SCR 981