the guards look for high criminal to put in jail! we dont know what crime the pony or creature but one thing is sure , let him or her free will make everypony or creature in danger! lucky for the guards is a criminal them face and beat and put in jail, is not a powerful enemy like chrysalis,sombra, tirek, discord ,starlight or storm king! of some of theme are reform or in tantarus! so is sample job for them but the most hard is to fond it! of course is the hard part! is not like the criminal will say * i am here and put me in jail!*