Lawyer creates obstacle restricting good person (9)
I believe the answer is:
barrister
'lawyer' is the definition.
(barrister is a kind of lawyer)
'obstacle restricting good person' is the wordplay.
'obstacle' becomes 'barrier' (barrier is a kind of obstacle).
'restricting' means one lot of letters goes inside another.
'good person' becomes 'st' (saint).
'barrier' going around 'st' is 'BARRISTER'.
'creates' is the link.
(Other definitions for barrister that I've seen before include "Legal representative" , "A bewigged legal eagle" , "Court lawyer" , "Legal counsel" , "American lawyer" .)