Opinion or Expert Evidence: Its Relevancy

Relevancy of opinion evidence

The relevancy of opinion evidence is dealt with in Sections 45 to 51 of the Indian Evidence Act (IEA).

Opinion evidence in general is inadmissible. But two kinds of opinion evidence have relevance and hence admissible in judicial proceedings: one is expert opinion and the other is opinion of non-experts in some exceptional cases, as specified in the IEA.

The witnesses are generally expected to tell the court the facts but not the opinions they form from the facts they have seen, heard or perceived. Forming the opinion is the prerogative of the court. It is a judicial act to be performed by the court alone. The duty of the witness is to depose but not to decide.

Expert opinion & its relevance

When the Court has to form its opinion upon a point of foreign law or of science or art, or as to identity of handwriting or finger impressions, the opinions of persons skilled in such areas of specialisation, are relevant. Such persons are called experts. In such matters an expert alone can give an opinion.

Expert is a person who is skilled in a particular art, trade or profession. An expert possesses special knowledge in his area of expertise. A doctor is an expert in medical science. A lawyer is an expert in legal matters. An accountant has special knowledge in accounting. The duty of the expert is to furnish the data with necessary scientific criteria so as to enable to come to an independent conclusion.

In matters in which ordinary people can form opinion, the expert opinion is inadmissible. The court must consider whether a witness is an expert witness or an ordinary witness. Even if a person is an expert witness, it is within the domain of the court to decide whether the opinion could be admitted or denied or how much weight it should be given. The evidence of the expert should be interpreted in the same manner as other evidence.

If the opinion of an expert is relevant, then the facts which support or rebut that opinion are also relevant (Section 46 IEA).

Opinion of Electronic examiner

On any matter relating to any information transmitted or stored in any computer resource or any other electronic or digital form, the opinion of the Examiner of Electronic Evidence referred to in section 79A of the Information Technology Act is relevant.

An Examiner of Electronic Evidence is an expert in matters referred to above.

Opinion on hand writing or signature

In proving handwriting or signature of a person, the opinion of any person acquainted with the handwriting or signature of the person, is relevant.

The opinion of the person who has seen the other person writing or signing the document is a relevant fact.

The science with regard to the identification of handwriting and signatures is not conclusive like that of identification of thumb impressions. But when ocular and circumstantial evidence is provided with due corroboration to the opinion of a handwriting expert, such an opinion can be relied on by the court.

If signature is not complicated forgery can be identified by using a magnifying glass as well. The court can compare the admitted handwriting with disputed writing, under Section 73 of the IEA. It is a matter of prudence not to use this section by the court in criminal cases, but in civil cases this section can be used whenever it is absolutely necessary.

In deciding electronic signature, the opinion of the certifying authority issuing electronic signature is relevant.

When ocular evidence and medical evidence remain inconsistent the former has great evidentiary value.

Opinion regarding existence of a custom

When the court has to make a decision in regard to the existence of any general custom or right, the opinions of persons who would be likely to know the existence of such custom or right, are relevant.

Opinion in regard to usages, tenets etc

When the court has to form an opinion as to the usages and tenets of any body of men or family, the constitution and government of any religious or charitable foundation, or the meaning of words or terms used in particular districts or by particular classes of people, the opinions of persons having special means of knowledge thereon, are relevant facts.

Opinion on relationship between persons

When the court has to take a decision in regard to the existence of relationship expressed by conduct of one person to another, the opinion of any person who has special means of knowledge on the relationship, is relevant.

A person familiar with a family can testify whether the members living together as a family behave like family members.

Grounds of opinion is relevant

Whenever the opinion of any living person is relevant, the grounds on which such opinion is based are also relevant.

Further reading

  1. The Indian Evidence Act, 11872
  2. The Law of Evidence by Ratanlan and Dhirajlal