Kautilya's Arthashastra 2.36.44

2.36.44

bandhanāgāre ca bālavṛddhavyādhitānāthānāṃ jātanakṣatrapaurṇamāsīṣu visargaḥ //

On the days to which the birth star of the king is assigned, as well as on full moon days, such prisoners as are young, old, diseased, or helpless (anátha) shall be let out from the jail (bandhanâgâra); or those who are of charitable disposition or who have made any agreement with the prisoners may liberate them by paying an adequate ransom.