My boyfriends dad gave him a TV in exchange for him to do some work. His dad has got himself another TV to take the old ones place. Now his dad is upset at my boyfriend for something and wants his TV back. We tried reasoning with him but he says if we don't return it he will call the cops and say we stole it. We do have texts saying he will call the cops if we don't bring it back, but is there anything legally he can do since he gave it to us in exchange for doing work on his house?

He can call the police and lie, depends if the police will believe dad or not.

But if the dad does not lie, no there is nothing he can do