In the late 19th century Congress began to employ a series of related strategies to advance various agendas for social reform and to protect states from what are sometimes called “federal” or “enclave” effects. Supreme Court decisions under the dormant Commerce Clause either undermined or cast grave constitutional doubt on the ability of states to exclude or regulate articles that might adversely affect their citizens’ health, safety, or morals where those articles had been introduced from other states through the channels of interstate commerce. Over time, Congress developed three ways in which to redress the dormant Commerce Clause disability under which the states labored, and to cooperate with the states in the enforcement of their police powers. One was to impose an outright prohibition on the interstate shipment of the article in question; a second was to prohibit shipment of the article into states in which its use or sale was prohibited; and a third was to “divest” the article of its interstate character upon its arrival in the destination state, thus allowing the state police power to apply earlier than dormant Commerce Clause doctrine would otherwise have allowed. 


These various uses of the commerce power as a “federal police power” were deployed to address a wide array of social problems and to promote the goals of a disparate collection of social reformers in the Progressive Era. Temperance reformers, opponents of gambling, conservationists, crusaders for pure food and drugs, enemies of the “white slave” trade, prison reformers, labor unions, and many others successfully secured and defended legislation advancing their objectives through such regulations of interstate transportation. This study will reconstruct their efforts and the doctrinal underpinnings of their successes, with the aim of better understanding the reasons for the one notable failure of this strategy of reform: the movement to regulate child labor. In the 1918 case of Hammer v. Dagenhart, the Supreme Court invalidated the Keating-Owen Child Labor Act of 1916, which prohibited the interstate shipment of goods manufactured by enterprises employing child labor. The study will trace the political and intellectual history of the efforts of child labor reformers, particularly leaders of the National Child Labor Committee, to achieve their objectives through this and other means: the war power; regulatory taxation; a failed constitutional amendment; codes of fair competition under the National Industrial Recovery Act; and, finally and successfully, under the Fair Labor Standards Act of 1938. Particular attention will be paid to cognate developments in the regulation of convict labor, and the manner in which those developments informed and shaped the strategies of those devoted to child labor reform.