The Prisoner who is jailed and concurrently facing Trial of his case in the Court is a one, who is under Trial Prisoner.

Generally, the Accused might be a foreigner or terrorist or a habitual offender and who once let out on Bail, chances are there he would flee, and securing his presence in the Court for conducting Trial is not only impossible but time consuming. Hence, the Court does not grant him Bail.

Otherwise, certain Special Statute like NDPS has specific provision barring those Accused from seeking Bail. Even in some cases the Court might have retained incriminating evidences against the Accused and those accused if let out on Bail might not only destroy evidences but also influence the Witnesses, hence they are jailed till the Police files Chargesheet or until prime Witnesses were examined by the Court.