In 1919, Congress passed the Child Labor Tax Law which constituted a ten percent tax on the profits of any company using child labor. The law defined “child labor” as the use of minors “under the age of sixteen in any mine or quarry, and under the age of fourteen in any mill, cannery, workshop, factory, or manufacturing establishment.” Additionally, the definition applied to the use of children in these age ranges for more than eight hours a day or six days a week, or during certain evening hours. Drexel Furniture Co. (plaintiff) brought suit in federal district court against Bailey (defendant). Drexel challenged the law on the ground that it was an unconstitutional attempt by the federal government to regulate child labor in the states–a function exclusively reserved to the states under the Tenth Amendment to the Constitution. The district court held the law unconstitutional and the court of appeals affirmed. The United States Supreme Court granted certiorari.