Expert Witness

Expert witness, an 'expert' is not a 'witness' of fact. His evidence is really of an advisory character. The duty of an 'expert witness' is to furnish the Judge with the necessary scientific criteria for testing the accuracy of the conclusions so as to enable the judge to form his independent judgment by the application of this criteria to the facts proved by the evidence of the case. The scientific opinion evidence, if intelligible, convincing and tested becomes a factor and often an important factor for consideration along with the other evidence of the case. The credibility of such a witness depends on the reasons stated in support of his conclusions and the data and materials furnished which form the basis of his conclusions, State of Himachal Pradesh v. Jai Lal, (1999) 7 SCC 280: AiR 1999 SC 3318 (3321). [Evidence Act, 1872, s. 45]