Idaho Code § 62-401: Checking baggage.

A check must be affixed to every package or parcel of baggage when taken for transportation by any agent or employee of a railroad corporation, and a duplicate thereof given to the passenger or person delivering the same in his behalf; and if such check is refused on demand, the railroad corporation must pay to such passenger the sum of twenty dollars ($20.00) to be recovered in an action for damages; and no fare or toll must be collected or received from such passenger, and if such passenger has paid his fare the same must be returned by the conductor in charge of the train; and on producing the check, if his baggage is not delivered to him by the agent or employee of the railroad corporation he may recover the value thereof from the corporation.