Hire someone to really steal something and plant it in the jerks car.
then report him.
Actually it wouldnt surprise me if in the end it was found out that this guy was doing a bit of stealing hiimself.
Remember hearing of a similar situation around here where a cop was hired to do pretty much the same thing at a grocery store and 6 months later he himself was arrested for stealing from the very store he was hired to prevent stealing from.
Beauty of it was. This cop on the street was known to be a real hard arse. The real gung ho type that would probably give his own mom a ticket for jay walking.
From what I hear its not at all an unsual occurance.
But I would wait and see if it happens again. If it does I would do as you are thinking and go visit the owner.
I've always found its best to meet this kind of situation head on.
If you quit without saying anything you will just look like you are running, and will also make you "look" guilty.
If they are looking to get rid of you they will find a reason anyway
Which may be the case. (coul be they just dont like you)
So I would indeed say something. Yet I'd still look for something else.
But dont just quit without saying anything.