Indeed the police made up their minds (7)
I believe the answer is:
decided
'up their minds' is the definition.
I can't tell whether this defines the answer.
'indeed the police' is the wordplay.
I cannot quite see how this works, but
'police' could be 'cid' (abbreviation for Criminal Investigation Department) and 'cid' is found in the answer.
The remaining letters 'deed' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'made' is the link.
Can you help me to learn more?
(Other definitions for decided that I've seen before include "Resolute; settled" , "Indisputable" , "unmistakable" , "Unquestionable" , "Made mind up, being unequivocal" .)