Section 62(5) in The Representation of the People Act, 1951
(5)No person shall vote at any election if he is confined in a prison, whether under a sentence of imprisonment or transportation or otherwise, or is in the lawful custody of the police:Provided that nothing in this sub-section shall apply to a person subjected to preventive detention under any law for the time being in force.Provided further that by reason of the prohibition to vote under this sub-section, a person whose name has been entered in the electoral roll shall not cease to be an elector.
