They're on your side till they decide you're not. Never tell anyone about the grow. Sometimes people will just get pissed off at you for some dumb reason and then all they have to do is drop a dime on you and the cops can come and use a no knock warrant and kick your door in and endanger anyone on the premises. Caution is required. Never believe what an officer says to your face because they are allowed by law to lie to you.