Check with the local authority that created that law or directly with your local police department. My city has a website and our Office of Short Term Rentals lists laws regarding guests. As a tourist in most European hotels I have been required to show my passport to prove identity. They usually write down my passport country of issue, number, expiration date and my name or they photocopy it. If no one answers your question and you cannot find anything on the Internet, ask a small hotel and they may have specific information for you. Good Luck.
