Company lawyer closing bars (4)
I believe the answer is:
coda
'closing bars' is the definition.
(I've seen this in another clue)
'company lawyer' is the wordplay.
'company' becomes 'co' (abbreviation).
'lawyer' becomes 'da' (abbreviation for District Attorney).
'co'+'da'='CODA'
(Other definitions for coda that I've seen before include "Passage concluding a musical piece" , "End piece written for a piece of music" , "Closing passage of a piece of music" , "Passage of piece of music added to the end" , "Concluding passage of piece of music" .)