Possible Clues:

• Working animal cooled down during game: good
• Very cold in game, shivering at the end, maybe I do a lot of sniffing
• Canine that helps law officers
• Why the hard-bitten crook gave himself up?
• It sometimes sniffs cocaine
• Canine for the boys in blue
• Watch over Jack Russell with Chief Barker on force
• School harbouring vermin, go over for busy helper
• German shepherd?
• Cop's canine companion