Oh, back in gaol, having misbehaved? He's thoroughly lawless (8)
I believe the answer is:
hooligan
But I can't explain it at all! Could you help me understand?
(Other definitions for hooligan that I've seen before include "Undesirable" , "Tough" , "Violent lout" , "Thug, ruffian" , "Wild ruffian" .)