What is the nondelegation doctrine?

The nondelegation doctrine is the constitutional principle that Congress may not delegate its core legislative power to another branch. The textual foundation is Article I, Section 1, which provides that 'All legislative Powers herein granted shall be vested in a Congress of the United States.' Because the Constitution vests legislative power exclusively in Congress, and because Congress may not surrender the functions it alone has been assigned, the doctrine holds that when Congress instructs an executive agency to make rules, it must lay down an intelligible principle that channels the agency's discretion. Without that guiding principle, Congress has in effect transferred lawmaking authority to the executive rather than delegating a bounded administrative function -- a structural violation of the separation of powers even if no other constitutional provision is expressly at issue. The doctrine has been recognized as a limit on federal power since the early republic, but the Supreme Court did not deploy it to strike down an act of Congress until 1935.

J.W. Hampton Jr. & Co. v. United States, 276 U.S. 394 (1928), established the intelligible principle standard that has governed delegation analysis ever since. The Tariff Act of 1922 authorized the President to adjust import duties to equalize production costs between the United States and competing foreign countries. Chief Justice William Howard Taft, writing for a unanimous Court, upheld the statute. Taft articulated the standard this way: if Congress lays down by legislative act an intelligible principle to which the person or body authorized to act is directed to conform, such legislative action is not a forbidden delegation of legislative power. The decision established that Congress could delegate broad discretion to executive officers so long as the enabling legislation provided a discernible objective or standard, even a quite general one, to bound the agency's choices. The intelligible principle test set the floor for permissible delegation, and nearly every subsequent delegation challenged before the Supreme Court has satisfied it.

A.L.A. Schechter Poultry Corp. v. United States, 295 U.S. 495 (1935), and Panama Refining Co. v. Ryan, 293 U.S. 388 (1935), remain the only two Supreme Court decisions striking down a federal statute as an unconstitutional delegation of legislative power. Both cases involved Title I of the National Industrial Recovery Act (NIRA), enacted in 1933 as part of the New Deal. Panama Refining, decided in January 1935, concerned Section 9(c) of NIRA, which authorized the President to prohibit interstate transportation of petroleum produced in excess of state quotas. Chief Justice Charles Evans Hughes, writing for an 8-1 Court, held that Section 9(c) provided no standard, rule, or condition to govern the President's decision whether to prohibit the shipment of so-called hot oil; the absence of any intelligible principle rendered the delegation unconstitutional. Schechter Poultry, decided in May 1935, involved Section 3 of NIRA, which authorized trade and industrial associations to draft 'codes of fair competition' subject to presidential approval and carrying the force of law. The Live Poultry Code for the New York City metropolitan area was one such code. A unanimous Court held Section 3 an unconstitutional delegation because Congress had provided no standard by which to judge whether the codes served the public interest -- the statutory phrase 'fair competition' was too indefinite to constitute an intelligible principle bounding the code-drafting process. The Court also held that the application of the Live Poultry Code to the Schechters exceeded Congress's Commerce Clause authority, so Schechter rested on two independent grounds. After these decisions, Congress revised subsequent legislation to provide more express standards for agency rulemaking, and no federal statute has been struck down under the nondelegation doctrine since 1935.

Since 1935 the intelligible principle test has been applied with great permissiveness. Yakus v. United States, 321 U.S. 414 (1944), upheld the Emergency Price Control Act of 1942, which authorized the Price Administrator to set maximum prices that would be 'generally fair and equitable' -- language barely more specific than the NIRA's rejected standards, but upheld in the context of wartime price controls. Whitman v. American Trucking Associations, 531 U.S. 457 (2001), upheld the Clean Air Act delegation authorizing EPA to set National Ambient Air Quality Standards at levels 'requisite to protect the public health' with an 'adequate margin of safety.' Justice Antonin Scalia's majority opinion, unanimous on the delegation question, acknowledged the breadth of the delegation but held that 'requisite to protect the public health' was an intelligible principle sufficient under Hampton. Scalia also rejected the argument that an agency could cure an otherwise unconstitutional delegation by adopting a narrowing construction of the statute; the intelligible principle must appear in the act of Congress, not in agency self-restraint. Justices William Rehnquist and Clarence Thomas wrote separately to suggest the Court should consider whether the intelligible principle test sets the bar too low and whether the stricter approach of Schechter and Panama Refining should be revived, but neither view commanded a majority. As of the 2028 election cycle, no statute has been struck down under the nondelegation doctrine since 1935.

West Virginia v. EPA, 597 U.S. 697 (2022), introduced the major questions doctrine as a distinct but related constraint on executive agency power. The case arose from EPA's Clean Power Plan, which interpreted Section 111(d) of the Clean Air Act to authorize the agency to restructure the national electricity generation system by shifting production from coal to natural gas and renewable sources -- a policy with vast economic and political significance. Chief Justice John Roberts, writing for a 6-3 Court, held that when an agency claims authority to resolve a major question of vast economic and political significance, the Court presumes that Congress did not intend to hide such a transformative power in broad or oblique statutory text, and the agency must point to clear congressional authorization for the specific action taken. The Court held EPA lacked that clear authorization and vacated the Clean Power Plan. The major questions doctrine is a statutory interpretation canon, not a direct nondelegation holding: it does not announce that the statute violated Article I, but rather that the statute, properly read, did not authorize what the agency claimed to do. Justice Neil Gorsuch, joined by Justice Samuel Alito, concurred separately and argued that the major questions doctrine is best understood as a reflection of nondelegation principles -- that when Congress acts through broad or vague statutory language in an area of major national importance, the intelligible principle requirement of Hampton should be scrutinized more rigorously. The 2028 relevance: every major agency rulemaking on climate, health care, immigration, and financial regulation is now subject to challenge under the major questions doctrine, and the Senate seats on the 2028 ballot determine which party controls the chamber that must supply the clear congressional authorization agencies will increasingly need to act.