Deed or legal proceeding (6)
I believe the answer is:
action
This clue is a double definition.
'deed' is the first definition.
(I've seen this before)
'legal proceeding' is the second definition.
(action is a kind of legal proceeding)
(Other definitions for action that I've seen before include "Battle or lawsuit, maybe" , "claim in court" , "Watch operating mechanism" , "A judicial proceeding brought by one party against another" , "Performance" .)