Indian Evidence Act
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This article has been written by Naman Sherstra, a student of Department of Law, University of Calcutta.


Chapter II of the Indian Evidence Act talks about the relevancy of opinion of the third person. It is also termed as an expert’s opinion which is broadly provided under Section 45- 51 of the act. The provisions under this section are exceptional to natural rule of law of evidence where the evidence is only that fact which is given by the witness on the basis of his knowledge and belief. This exception states that the court cannot draw its opinion on the technical matters as well as complicated matters which require the special knowledge of the person having acquired expertise on the relative field. The conditions for the demand of the expertise include the situation where the case cannot be solved without the help of the expert. The witness who is expressing its opinion is an expert of the particular field.

Expert explanation

Section 45 of the Indian Evidence Act provides information about the definition of expert. An expert is said to be a person having knowledge or expertise in any of the field like foreign law, science, art, identity of handwriting or finger expression and where such knowledge has been gathered by him by practice, observation, studies. For example- Medical Practitioner, technical experts, chemical and explosive experts, ballistic expert and fingerprint expert. The evidence of points is admissible when he takes the court into complete belief. The opinion of the expert has to be given orally only, certificate as well as report is not accepted as evidence. However, the definition of expert under section 45 is not only extended to the five fields as mentioned in the section. There are also other certain fields where the courts may seek the opinion of the expert.

Duty of the expert

The primary obligation of the expert witness is to assist the court on the cases which fall under the ambit of their expertise. They are not bound to compel the parties to pay their fees who have appointed them. There is a common perception that the clients who appoint the expertise make their expert lean towards themselves hence making their cases favourable. The compromise with the independence of the expert may turn down the appointment.

Expert opinion Value

There are two aspects of the expert evidence. Data evidence and Opinion evidence, generally data evidence, are accepted until they vary the oral evidence. The second one opinion evidence is drawn from the data and it would not get precedence over the direct eyewitness testimony unless the inconsistency between the two is so great as to falsify the oral evidence. In S. Gopal Reddy vs State of Andhra Pradesh the Hon’ble Supreme Court held that the evidence given without any independent corroboration is rather difficult to accept.

Expert evidence is opinion evidence and it cannot replace the substantive evidence. It is the rule of the procedure that the expert witness must be corroborated either by direct evidence or by circumstantial evidence. It is always safe to rely upon such evidence with an independent and reliable corroboration.

Evidence of expert witness v evidence of ordinary witness

The expert witness only provides opinion regarding the handwriting, fingerprinting, nature of injury technical inquiry whereas an ordinary witness states the fact relating to the incident happened. The nature of the expert witness is advisory whereas the witness states the facts to the court. The opinion of the witness is not admissible in the court. The accountability of ordinary witnesses is always considered more over the expertise witness.

Handwriting expert opinion

When the court is of opinion to take the handwriting of any person, or the opinion of any person having expertise of handwriting admissible as evidence the person himself shall have to give the opinion that if the handwriting has been written by him or not.

The handwriting of a person may be proved in the below given ways:

  1. Evidence provided by the writer himself.
  2. Evidence provided by a person who has seen the person, whose handwriting is in question in writing.
  3. A person who has received any document which is written by the person whose handwriting is in question or under the authority of such person addressed to that person.
  4. A person who is expert in comparing handwriting.
  5. A person who is acquainted with the signatures and writing of that person.
  6. A certifying authority who has issued the signature when the court has formed an opinion to the digital signature of the person as mentioned under section 47-A of the Act.
  7. When the Court compares the documents in question with the other documents which are proved genuine in the court as mentioned in section 73.
  8. In the case of doubtfulness the court may ask the person to write something in the face of court to compare it with the document.

Opinion for electronic evidence

When in a proceeding the court has to form an opinion on any matter relating to any information transmitted or stored in any computer resource or any electronic resource or any other electronic or digital form, the opinion of the person taken in such cases is known as examiner of electronic evidence. The examiner of electronic evidence is known as the expert in such cases. For this section, electronic evidence includes any information transmitted or stored in any computer resource or any other electronic or digital form, the opinion of the examiner of the electronic evidence referred to in section 79A of the Information and Technology Act, 2000(21 of 2000), is a relevant fact.

Opinion for foreign law

When it is necessary to form an opinion as to the law of the country, statements of such law published in a book published under the authority of the Government of that country and the reports of the cases decided by the courts of that country and contained in the books purporting to be reports of such rulings, are relevant, that is may be referred to by the court. A statement contained in an unauthorized translation of the Code Napoleon as to what the French law is on a particular matter. The opinion of such experts can be taken under Section 4 of the Act. However, the other reports of the ruling of the court can also be taken as relevant which are given in such books of foreign law.

Foreign law in India is always considered as the question of fact. There have been the cases where the court has interpreted personal laws as Indian Laws and thus are the laws of the land. Therefore, the court does not require a person to interpret the laws as the courts can do tasks on their own.
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Opinion for fingerprint

The evidence given by a fingerprint expert need not necessarily be corroborated; but the courts must satisfy itself as to the value of the other evidence. Generally, a finger impression expert’s opinion is given more weightage because it remains the same from his birth to his death and no other fingerprint can match with the one. Where the Court has to determine the credibility of the fingerprint expert the court can review his past credential records as well as work records. In case of being found suspicious the court can deny to entertain such evidence. 

The evidence of the fingerprint expert is not substantive evidence. It can only be used to corroborate some items of substantive evidence, which are otherwise on record. Fingerprint studies have been given a higher importance these days but the court has been reluctant to accept that as a piece of evidence. A person who is a fingerprint expert is said to match two fingerprints thereafter the opinion of such expert is relevant and admissible in court.

Opinion for Science and art

The aforementioned words include all subjects on a course where special study and experience is needed to make an opinion. The word science is very broad in practical use and they are not only limited to the higher sciences similarly the term art is also not limited to the fine arts but also it extends to the person having skills of handicraft, trade, profession and skill in work which, with the advance of culture has been carried beyond the sphere of common pursuits of life into that of artistic and scientific action.

To construe that if any expertise comes under the ambit of ‘art’ and ‘science’ the following tests can be applied.

The subject matter of injury such that inexperienced people are not capable of forming a correct judgement without the assistance of the experts.

The character of the science or art is such that it requires a course or a study to obtain a competent knowledge or skill in the field.

The study of certain customs and manners of tribes and castes, of the areas occupied by them and of other connected matter comes under the ambit of the science or art under this section. The tests which may be applied in determining whether a particular question is one of the scientific nature and consequently whether skilled witnesses may pass their opinion upon it are: Is the subject matter of enquiry such that inexperienced men are unlikely to prove capable of forming a correct judgement upon it without the assistance of the experts; that is does it so far partake of the character of a science or art as to require a course of previous habit or study in order to obtain a competent knowledge of its nature, Books dealing with customs and manners of different castes and tribes are admissible in evidence to prove them.

Every science has its own technical terms, which are so much Greek or Hebrew to the average juryman. What would the normal person can answer to the question whether a certain dose of a prescription containing choral would have been dangerous.

Opinion of medical expert

In the medical cases the opinion of the medical expert is required. In criminal matters the victim as well as the accused is examined. When the court requires the opinion of a medical expert in the cases which involve medical technicalities it asks the medical expert to express its opinion on the cases. The medical opinion may involve the physical condition of the person, his age, cause of death of the person, nature and effect of disease, time of death, nature of instrument used for causing death, symptoms and time of death, future consequences of the death. In the case of rape the medical evidence possess a great importance as if the opposite counsel thinks that the rape was consensual the skin cells and scratches on the body may prove an important aspect in the decision of the case. But there is a problem with these experts is that they are always called by a party who are having the evidence in their favour. That is why the court has to rely upon the opinion of the expert though they have to consider being impartial while expressing their opinion.

The Evidentiary value of medical cases is only corroborative and not conclusive and hence in the case of conflict between oral evidence and medical evidence the former is to be preferred unless the medical evidence completely rules out the oral evidence.

Opinion of ballistic expert

Ballistic experts, also known as firearms experts are people who are experts in the study of projectiles and firearms. The Ballistic expert may trace the bullet or cartridge to a particular weapon from which it was fired. The opinion of the ballistic expert is only taken into consideration when he furnishes the report before the court. 


The expert witness is totally different from the ordinary witness. The expert’s opinion can never be questioned in the courtroom. In the case of question over the ability and knowledge of the expert the opinion or report is brought into question. The expert opinion is judged from a different view as he is unaware about the facts of the case and the court is unaware about the field of expertise the case is related to.

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