Despite the vigorous debate which it occasioned in other circles, the practice of delegating legislative power to regulatory agencies which began at the end of the nineteenth century was never seriously questioned by American courts during the progressive era. This is not to say that the judiciary saw no threat posed by government by institutions of a form undreamed of at the time the Constitution was framed. Since the appearance of the first regulatory commissions, the courts have shown a concern to protect individual rights which recently may be seen in the insistence on procedural safeguards in agency adjudication and rulemaking which informs the Administrative Procedure Act. But the judicial branch at the turn of the century was little troubled by the absence of democratic input into the regulatory comnussion's rulemaking process, for the courts saw the same threat--subjection of individual rights to uncontrolled majority interests--posed by regulatory comnussion and legislature alike. Judicial response consequently took form not in a remand of non-delegable powers to the legislature, but in the doctrines of the non-finality of administrative and legislative action, and in efforts to narrow and define the constitutionally permissible scope of such action.
John H. Garvey, Judicial Consideration of the Delegation of Legislative Power to Regulatory Agencies in the Progressive Era, 54 IND. L. J. 45 (1978).