The (8,7) has come to me. It's LAWRENCE DURRELL (underwearcellar **)
Funnily enough, I had an I at the end of the (5,8) purely because the intersecting grid had an I for this clue:-
""Quickly putting away spliff, go in oh so dopey" (9,3) I assumed it was an anagram as follows:-
POLISHING OFF from (SPLIFF GO IN OH)
However, Petty Criminal looks er OK for someone who commits a minor violation!!!!