Someone may have suggested the magistrates office as a route to acquire a court order to keep them off the property. If they violate a court order, it's possible at that point the police may have the authority to get involved.
You could install a physical gate of some sort (opened by a garage door opener or similar device) as a physical block to your driveway. If they damage that, the police could be called and the company potentially charged with vandalism.
If it were me I'd call a local lawyer and at least have a meeting to go over what options I might have.
Good luck.

