Act restricting police department is agreed (7)
I believe the answer is:
decided
'agreed' is the definition.
Both the answer and definition are adjectives. Perhaps there's a link between them I don't understand?
'act restricting police department' is the wordplay.
'act' becomes 'deed' (deed is a kind of act).
'restricting' means one lot of letters goes inside another.
'police department' becomes 'CID' (abbreviation for Criminal Investigation Department).
'deed' enclosing 'cid' is 'DECIDED'.
'is' acts as a link.
Can you help me to learn more?
(Other definitions for decided that I've seen before include "Made mind up, being unequivocal" , "Resolute; settled" , "Definite; agreed" , "Indisputable" , "unmistakable" .)