15 U.S.C. § 1001

Every film or other pictorial representation of any prize fight or encounter of pugilists, under whatever name, transported into any State, Territory, or possession, for use, sale, storage, exhibition, or other disposition therein is divested of its character as a subject of interstate or foreign commerce to the extent that it shall upon crossing the boundary of such State, Territory, or possession, be subject to the operation and effect of the laws of such State, Territory, or possession enacted in the exercise of its police power.