Without knowing these, I can see two potential defense to get you off:
1. Since the prostitutes were really police, technically you did not let prostitutes rent the room. It is legally impossible.
2. Entrapment, which many jurisdictions require that the criminal intent is a product of imporoper police behavior and the plaintiff is not pre-disposed to commit the crime. In CA, the police mis-conduct must be outrageous and the police instigates the crime.