United States v. Darby

Writing for a unanimous Court, Justice Stone upheld the act as an appropriate exercise of Congress's power to regulate interstate commerce. First, however, he had to address a Supreme Court precedent that pointed the other way. In Hammer v. Dagenhart (1918), the Court struck down federal legislation aimed at controlling child labor. Based on the Commerce Clause, the Child Labor Act was found to be an infringement on the powers reserved to the states in the Tenth Amendment. A bare majority of the justices had voted against the law, with Oliver Wendell Holmes writing an important dissenting opinion in which he stated that the commerce power allowed Congress to regulate not just products shipped through interstate commerce, but their effects. It was the Holmes dissent that Stone alluded to now:

In that case . . . the powerful and now classic dissent of Mr. Justice Holmes [set] forth the fundamental issues involved, that Congress was without power to exclude the products of child labor from interstate commerce. The reasoning and conclusion of the Court's opinion there cannot be reconciled with the conclusion which we have reached, that the power of Congress is plenary to exclude any article from interstate commerce subject only to the specific prohibitions of the Constitution . . . The conclusion is inescapable that Hammer v. Dagenhart, was a departure from the principles which have prevailed in the interpretation of the commerce clause both before and since the decision and that such vitality, as a precedent, as it then had has long since been exhausted. It should be and now is overruled.

The decision did not put an end to the controversy. While Darby established the constitutionality of the Fair Labor Act, there still remained some confusion about whether it covered employees who engaged who engaged "in commerce" or "in the production of goods for commerce." In Maryland v. Wirtz (1968), the Court ruled that the act also covered state employees. Eight years later, however, in National League of Cities v. Usery (1976), the Court overturned Wirtz and revived the rule of Hammer v. Dagenhart to say that state and municipal employees were not covered by the Fair Labor Act. Then in 1985, the Court revisited the issue in Garcia v. San Antonio Metropolitan Transit Authority (1985), overruling Usery.