Expert opinion

Ramesh Chandra Agrawal v. Regency Hospital Ltd., (2009) 9 SCC 709 

18. The importance of the provision has been explained in State of H.P. v. Jai Lal [(1999) 7 SCC 280 : 1999 SCC (Cri) 1184] . It is held, that, Section 45 of the Evidence Act which makes opinion of experts admissible lays down, that, when the court has to form an opinion upon a point of foreign law, or of science, or art, or as to identity of handwriting or finger impressions, the opinions upon that point of persons specially skilled in such foreign law, science or art, or in questions as to identity of handwriting, or finger impressions are relevant facts. Therefore, in order to bring the evidence of a witness as that of an expert it has to be shown that he has made a special study of the subject or acquired a special experience therein or in other words that he is skilled and has adequate knowledge of the subject.

19. It is not the province of the expert to act as Judge or Jury. It is stated in Titli v. Alfred Robert Jones [AIR 1934 All 273] that the real function of the expert is to put before the court all the materials, together with reasons which induce him to come to the conclusion, so that the court, although not an expert, may form its own judgment by its own observation of those materials.

20. An expert is not a witness of fact and 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 these 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 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 material furnished which form the basis of his conclusions. (See Malay Kumar Ganguly v. Dr. Sukumar Mukherjee [(2009) 9 SCC 221 : (2009) 10 Scale 675] , SCC p. 249, para 34.)

21. In State of Maharashtra v. Damu [(2000) 6 SCC 269 : 2000 SCC (Cri) 1088 : AIR 2000 SC 1691] , it has been laid down that without examining the expert as a witness in court, no reliance can be placed on an opinion alone. In this regard, it has been observed in State (Delhi Admn.) v. Pali Ram [(1979) 2 SCC 158 : 1979 SCC (Cri) 389 : AIR 1979 SC 14] that "no expert would claim today that he could be absolutely sure that his opinion was correct, expert depends to a great extent upon the materials put before him and the nature of question put to him".

22. In the article "Relevancy of Expert's Opinion" it has been opined that the value of expert opinion rests on the facts on which it is based and his competency for forming a reliable opinion. The evidentiary value of the opinion of an expert depends on the facts upon which it is based and also the validity of the process by which the conclusion is reached. Thus the idea that is proposed in its crux means that the importance of an opinion is decided on the basis of the credibility of the expert and the relevant facts supporting the opinion so that its accuracy can be crosschecked. Therefore, the emphasis has been on the data on the basis of which opinion is formed. The same is clear from the following inference:

"Mere assertion without mentioning the data or basis is not evidence, even if it comes from an expert. Where the experts give no real data in support of their opinion, the evidence even though admissible, may be excluded from consideration as affording no assistance in arriving at the correct value."

23. Though we have adverted to the nature of disease and the relevancy of the expert opinion, we do not think it necessary to go into the merits of the case in view of the course we propose to adopt, and in view of the fact that the Commission is the last fact finding authority in the scheme of the Act.