In today's context of expanded human mobility, an individual's right to travel from, through, or to any of the United States without state restriction on or regulation of his admission or departure enjoys well-settled constitutional protection originating from two distinct sources. The interstate transportation of persons is governed by the commerce clause under which state power to regulate and tax the admission and departure of interstate passengers is restricted, but not entirely forbidden.
State Taxation of Interstate Travel: Alternative Constitutional Limitations,
U. Rich. L. Rev.
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