A witness is a person who gives evidence or testimony before any tribunal. Witnesses can be the people or experts with valuable input for the case.
Section 118 of the Indian Evidence Act generically lays down who may testify: All persons shall be competent to testify unless the Court considers that they are prevented from understanding the question put to them, or from giving rational answers to those questions, by tender years, extreme old age, disease, whether of body or mind, or any other cause of the same kind.
According to this Section, close relatives are not debarred from being witnesses in the Court of law. Therefore, the close relatives (father, mother, brother, maternal uncle) as well as the other witnesses (the doctor and the I.O.) are competent to testify and can appear as witnesses in the case. You should consult an expert to help you in this regard.
-Regards
Advocate Pooja
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