During the Progressive Era, public sentiment in the United States turned against what was perceived as increasingly intolerable child labor conditions.

In his majority opinion, Justice William R. Day struck down the Keating–Owen Act, holding that the Commerce Clause did not give Congress the power to regulate working conditions.

During the Progressive Era, public sentiment in the United States turned against what was perceived as increasingly intolerable child labor conditions.

He saw children growing up stunted mentally (illiterate or barely able to read because their jobs kept them out of school) and physically (from lack of fresh air, exercise, and time to relax and play).

Roland Dagenhart, who worked in a cotton mill in Charlotte, North Carolina with his two sons, sued, arguing that this law was unconstitutional.

That placed the entire manufacturing process under the purview of Congress, and the constitutional power "could not be cut down or qualified by the fact that it might interfere with the carrying out of the domestic policy of any State".

[5] Holmes also took issue with the majority's logic in allowing Congress to regulate goods themselves regarded as immoral, while at the same time disallowing regulation of goods whose use may be considered just as immoral in a more indirect sense: "The notion that prohibition is any less prohibition when applied to things now thought evil I do not understand ... to say that it is permissible as against strong drink but not as against the product of ruined lives.

"[6] At the time, the Eighteenth Amendment, banning the sale, manufacture and transport of alcoholic drink, had been approved by Congress and was being ratified by the states.

They also recast the reading of the Tenth Amendment, regarding it as a "truism" that merely restates what the Constitution had already provided for, rather than offering a substantive protection to the States, as the Hammer ruling had contended.