Interesting articles : Article 20(3) Constitution of India

A20(3) - Extends certain protection to a person in respect of the conviction for offence and sub-clause(3) thereof provides that no person accused of any offence SHALL be compelled to be witness against himself.

No person accused of any offence SHALL be compelled to be witness against himself.

Protection ONLY extent of being witness against himself
Does not include merely the mechanical process of producing documents in court which may throw a light on any of the points in controversy.
But which do not contain any statement of teh accused based on his personal knowledge.
Testimony by an accused may be said to have been self incriminatory

it must be of such a character that by itself it should have the tendency of incriminating the accused, if not also of actually doing so
it should be statement which makes the case against the accused person at least probable considered by itself

Conveying information based upon the personal knowledge of the person giving the information

Does not mean that he is asked to testify against himself.
No opportunity of hearing to accused is necessary in issuing such direction
Since power exist with the Magistrate to issue a direction to give voice sample during investigation and such direction are not violation of A20(3)
UNLESS accused in a position to show that any prejudice is caused with the direction
Voice samples are taken only for comparison , cannot be said to be witness against himself.

During Investigation stage - petitioner right under A20(3) is NOT violated
Specimen handwriting. or signature or finger impression by themselves are no testimony at all being wholly innocuous because they are unchangeable except in rare cases where the ridge of finger or the style of writing have been tampered with with.
Purpose served by handwriting, signature, DNA, Voice samples

They are ONLY materials for comparison in order to lend assurance to the court that its inference based on other material is reliable.
They are neither oral nor documentary evidence but belong to 3rd category of material evidence which is outside the limit of testimony.

11 Judge Bench of SC
The giving of finger impression or of specimen signature or of handwriting strictly speaking is not to be a witness.
To be a witness means imparting knowledge in respect of relevant fact, by means of oral statements or statements in writing by a person who has personal knowledge of the facts to be communicated to a court or to a person holding an enquiry or investigation.
A person is said to be a witness to a certain state of facts which has to be determined by a court or authority authorised to come to a decision, by testifying to what he has seen, or something he has heard which is capable to being heard and is not hit by the rule excluding hearsay or giving his opinion as an expert in respect of matters in controversy.
Evidence has been classified by text writers into 3 categories

20(3) covers oral testimony, written statements which may have a bearing on the controversy with reference to the charge against him
The accused may have documentary evidence which may throw some light on the controversy. If it is a document, which is not his statement conveying his personal knowledge relating to the charge against him, he may be called upon by the court to produce the document in accordance with Section 139 of Evidence Act.
Which in terms, provides that a person may be summoned to produce a document in his possession or power and that he does not become a witness by mere fact that he has produced it. and therefore he cannot be cross-examined.

3 J bench of SC
Until explicit provisions are engrafted in CrPC by Parliment, a Judicial Magistrate must be conceded the power to order a person to give a sample of his voice for the purpose of investigation of a crime
Such power has to be conferred on a Magistrate by a process of Judicial interpretation and in exercise of jurisdiction vested in the court u/s A142 of Constitution of India

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