Why Hotels Check Your ID ...and who gets to see it.

If you’re a privacy-conscious traveler, you may have wondered from time to time why hotels ask for ID when you check in, or why they ask you to give them the make and model of your car and other information that isn’t essential to the transaction. What’s the ID-checking for? ...

DIY ID card

Well, in many jurisdictions around the country, that information-gathering is mandated by law. Local ordinances require hotels, motels, and other lodgers (such as AirBnB hosts) to collect this information and keep it on hand. These laws also require that the information be made available to the police on request, for any reason or no reason, without a warrant.
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Extra...
13 Things Your Hotel Front Desk Clerk Won't Tell You