Unprofessional cop openly pockets a little drink (7)
I believe the answer is:
alcopop
'drink' is the definition.
(type of alcoholic drink)
'unprofessional cop openly pockets a little' is the wordplay.
'a little' indicates the answer is hidden within the clue (a little bit of the clue).
'ALCOPOP' can be found hidden inside 'unprofessional cop openly pockets'.
(Other definitions for alcopop that I've seen before include "Intoxicating beverage tasting like a soft drink" , "Soft drink containing spirits" , "Liquor drink for kids" , "drink young people like" , "drink favoured by youngsters" .)