The statement sounds appealing because it treats consent as if it were a switch the accused alone controls, but that is not how Selvi v. State of Karnataka (2010) actually works.
Consent removes the constitutional bar under Article 20(3); it does not create a new right. Once an accused agrees to a narco-analysis test, the state is no longer compelling them, so the test becomes permissible to conduct. That is very different from saying the accused can force the investigating agency, or a court, to arrange the test simply because they want it done.
The Supreme Court was explicit that narco-analysis is scientifically unreliable as a method of establishing truth, since a person's memory and speech can be distorted under the drug regardless of whether they intended to lie. A technique the Court itself distrusts is not one it will hand over as an entitlement to either side of a criminal case.
In practice, narco-analysis can only proceed with the accused's informed consent, agreement of the investigating agency, and, generally, judicial sanction with the safeguards Selvi laid down, such as the presence of a lawyer and recording of the procedure. None of that adds up to an absolute right for the accused to demand the test.
The statement is therefore false: consent is a necessary condition for the test to happen, not a guaranteed right to have it happen.
Breaking the claim into a short logical chain shows exactly where it fails.
Premise one.The refusal side of Selvi is real; the demand side that the statement asserts is not, so the correct evaluation of the statement is false.
\[ \boxed{\text{False.}} \]