In 1883, the Supreme Court, having already limited the Fourteenth Amendment's protections of the rights of freedmen, declared the Civil Rights Act of 1875 unconstitutional on the ground that it was “repugnant to the Tenth Amendment” (Civil Rights Cases, p. 15). During the next generation, the Court struck down a number of state exercises of the police power—in keeping with the Tenth Amendment's “prohibited by it to the states” clause—yet it never once allowed Congress to exercise a police power itself.
Erosion of the Tenth Amendment began early in the twentieth century. In 1895 Congress passed an act forbidding the shipment of lottery tickets in interstate commerce. The purpose was only nominally a regulation of commerce: its real purpose was to restrict gambling, a matter that had always been the exclusive domain of the states. In Champion v. Ames (1903), the Supreme Court upheld the act. The next year, the Court in McCray v. United States upheld a congressional act imposing a prohibitive excise tax on oleomargarine, which amounted to an exercise of a police power to protect the health of the citizenry, under the guise of a constitutional exercise of the power to levy taxes for the “general welfare.”
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