pba: The fact of the matter is that your car is on their private property. So their towing your property off of their property is not a criminal violation regardless whether the civil laws should preclude their towing it off (since they invited you unto their property.)
It is solely a civil violation on their part if they wrongfully towed your vehicle off their property, in violation of Department of Consumer Affairs regulations when a vehicle can be towed off a property. The cops generally cannot get involved even if there is a violation of the consumer regulations.