Communication

he Supreme Court correctly ruled that the President cannot impose tariffs without clear congressional approval. This paper argues that the Constitution assigns this power to Congress, and the Court’s decision upholds that foundational principle. Some commentators view the ruling as a betrayal of President Trump and the country, but this misses the real issue: the case was not about the wisdom of tariffs or trade deficits, but whether the President may impose tariffs without explicit congressional authorization.

The Supreme Court’s answer was grounded in the Constitution itself. By ruling that the International Emergency Economic Powers Act (IEEPA), a 1977 law that grants the President certain powers during national emergencies, does not authorize presidential tariffs, the Court reaffirmed one of the central structural principles of American government: the separation of powers between the legislative and executive branches. Separation of powers means that Congress (the legislative branch) makes laws, while the President (the executive branch) enforces them.

The Constitution is unequivocal about who holds tariff power. Article I, Section 8 assigns Congress the authority:

Tariffs fall squarely within the category of duties and imposts. Historically, they were among the federal government's main sources of revenue in the early United States. Because tariffs act as taxes on imported goods, imposing them has always been treated as part of Congress’s taxing power.

The Framers put this power in Congress. In Federalist No. 48, Madison stressed that taxation must remain in the branch closest to the people. He argued that control over taxes must be democratic.

Thus, the Constitution does not grant the President inherent tariff authority. Even the federal government conceded that the President lacks independent constitutional power to impose tariffs during peacetime. The administration’s tariffs should only be valid if Congress explicitly granted that power by statute.

The administration relied on the International Emergency Economic Powers Act (IEEPA).

Congress enacted IEEPA in 1977 as part of a broader reform of emergency economic powers. The law allows the President to respond to national emergencies involving foreign economic threats by regulating certain types of financial and commercial transactions.

Under IEEPA, the President may investigate foreign transactions, block property interests, regulate foreign exchange, and restrict certain types of imports or exports involving hostile actors. These powers allow the President to respond quickly to international crises such as sanctions violations, terrorism financing, or hostile foreign economic activity. Sanctions refer to penalties imposed on countries or individuals to influence their behavior.

The statute lists the President’s powers, including: investigating foreign transactions, blocking assets, regulating foreign exchange, and restricting specific imports or exports.

It is significant that this list omits any mention of tariffs or duties.

The administration argued that the statutory authority to "regulate importation" implicitly includes the power to impose tariffs. The Supreme Court disagreed.

Chief Justice Roberts made clear that courts are not in the habit of finding sweeping delegations of power in vague language. As the majority stated, "Congress does not alter the fundamental details of a regulatory scheme in vague terms or ancillary provisions." Congress issues explicit delegations when major economic powers, particularly taxation, are involved. The opinion is unambiguous: "If Congress had intended the President to have authority to impose tariffs under IEEPA, it would have said so with clarity." The total absence of any tariff reference to tariffs in IEEPA strongly suggests that Congress never intended to grant such power.

The Court correctly concluded that IEEPA authorizes the President to regulate limited economic transactions during emergencies, but never to impose tariffs.

Another important legal principle supporting the Court’s decision is the Major Questions Doctrine. This doctrine means that when the executive branch claims authority to make decisions of vast economic or political significance, such as creating nationwide regulation or new major rules, courts require that Congress has given clear and explicit permission for such authority.

Tariffs remain powerful economic tools. They reshape entire industries, alter international supply chains, influence diplomatic relations, and directly affect the prices millions of consumers pay. When applied widely, tariffs have vast economic consequences.

Precisely because of their sweeping impact, tariffs are major policy choices, not routine administrative actions. Under the Major Questions Doctrine, the Court demands explicit congressional clarity before it will permit the executive such broad authority.

The phrase “regulate importation” simply does not provide the clarity required to authorize a nationwide tariff policy. In law, clear congressional authorization means Congress must state its intentions plainly. If Congress had intended to delegate such authority through IEEPA, it would have said so directly.

The history of American trade legislation leaves no doubt. When Congress grants the President tariff authority, it always uses unambiguous statutory language and clear procedures.

Several major trade laws demonstrate this pattern.

The Tariff Act of 1930 established detailed tariff schedules and enforcement procedures.

The Trade Expansion Act of 1962, particularly Section 232, explicitly allows the President to impose tariffs when imports threaten national security.

The Trade Act of 1974, including Section 301, authorizes the President to impose tariffs in response to unfair trade practices.

Each of these statutes contains explicit language granting tariff authority and includes procedural safeguards such as investigations, consultations, and reporting requirements.

This absence in IEEPA is significant. Congress knew how to give the President tariff authority and did so in other statutes. Its omission in IEEPA supports the Court’s conclusion that the law does not allow presidential tariffs.

The decision aligns squarely with Supreme Court precedent, which consistently underscores Congress’s central and exclusive role in tariff policy.

Several important cases illustrate this principle.

In Field v. Clark, the Supreme Court upheld a statute that authorized the President to suspend tariff exemptions when foreign countries imposed unfair trade barriers on American goods. However, the Court noted that Congress itself had established the tariff framework and merely allowed the President to implement conditional adjustments.

This case established that tariff policy originates and remains with Congress. The President acts only within the boundaries Congress draws.

In J.W. Hampton Jr. & Co. v. United States, the Court upheld the Tariff Act of 1922, which allowed the President to adjust tariffs within specified limits. Importantly, the Court explained that Congress must provide an “intelligible principle”—a clear guideline or standard—guiding executive action.

This case confirms that while Congress may delegate tariff authority, it must always clearly define the limits of that delegation.

Although not a tariff case, Youngstown remains one of the most important separation-of-powers decisions in American history. In that case, the Supreme Court rejected President Truman’s attempt to seize steel mills during the Korean War.

As Justice Robert Jackson emphasized, executive power is at its absolute weakest when the President acts without congressional authority.

The Trump tariff case falls squarely into this category. Without unmistakable congressional authorization under IEEPA, the President lacked the necessary authority.

In Whitman, the Court reaffirmed that Congress cannot delegate major legislative powers through vague statutory language. Agencies and the executive branch may implement laws, but they cannot exercise broad policymaking authority unless Congress clearly authorizes it.

This principle compels the majority’s conclusion that vague standards such as “regulate importation” cannot be interpreted as broad grants of tariff power.

The dissenting justices argued that historically, the phrase "regulate importation" has sometimes been interpreted broadly enough to include tariffs. They referenced instances like President Nixon’s 1971 import surcharge, arguing that during national emergencies, the President needs broad authority to act quickly to protect the country, a point reiterated in recent court discussions, such as the U.S. Court of Appeals for the Federal Circuit's ruling on former President Trump’s use of emergency powers, according to the Associated Press. According to the dissent, Congress has at times granted the executive branch broad authority to address foreign financial problems, and past practice supports a realistic approach to statutory interpretation. They contended that the statutory text and structure do not explicitly rule out the use of tariffs and that the context of emergency powers justifies a more expansive reading. The dissent argued that their interpretation was consistent with historical practice and the essential need for effective executive action during crises. However, a Supreme Court decision clarified that the International Emergency Economic Powers Act does not give the President authority to impose tariffs. The examples cited by the dissent, such as the Nixon surcharge, rest on statutes with different structures or historical situations, making them less directly applicable to interpreting IEEPA. Although flexibility in emergencies can be important, the Constitution's structure and the principle of separation of powers are designed to prevent the concentration of major economic authority in the executive free of clear legislative direction. The assertion that past practice justifies a more pragmatic statutory reading risks jeopardizing Congress's constitutional role. Furthermore, the mere absence of a prohibition in statutory text acts not equivalent to a valid delegation of taxing authority, especially in the absence of any explicit reference to tariffs. In this way, while the dissent's pragmatic and historical approach has strengths, it ultimately cannot overcome the clear constitutional and statutory allocation of authority required in matters as significant as tariffs.

However, the majority found this reasoning unconvincing. Past executive actions and lower court decisions cannot redefine statutory language when Congress itself did not clearly delegate the power in question.

The dissent’s argument ultimately relied on historical practice rather than statutory text. The majority, by contrast, relied on the Constitution’s allocation of powers and the actual language of the law.

The case also implicates the non-delegation doctrine, which limits Congress’s ability to transfer its core legislative powers to another branch of government.

While Congress may authorize executive agencies to implement laws, it cannot casually transfer its most fundamental constitutional powers—especially taxation—without clear guidance and limitations.

If the Court had accepted the administration’s interpretation of IEEPA, it would effectively allow the President to impose tariffs of unlimited size, duration, and scope simply by declaring an emergency. By comparison, other major emergency statutes, such as the National Emergencies Act and the Defense Production Act, typically contain specific process requirements, time limits, or provisions ensuring congressional oversight. These safeguards are designed to prevent the indefinite or unchecked use of emergency powers by the executive branch. The absence of such explicit constraints in IEEPA makes the potential for broad presidential tariff authority especially significant.

Such a result would dramatically shift one of Congress’s most important constitutional powers to the executive branch.

The Court declined to interpret the statute in a way that would create that outcome.

The Supreme Court’s ruling does not prevent the United States from imposing tariffs. Congress retains the authority to establish tariffs directly or to delegate that authority to the President through clearly written statutes. However, in practice, this decision will likely prompt future presidents to act more cautiously when invoking emergency economic powers, knowing that courts may scrutinize the statutory basis for major actions such as tariffs. At the same time, Congress may need to draft economic or emergency legislation with more specific language to clearly authorize or limit executive actions in trade. As a result, we may see increased attention to clarity and particularity in future statutory delegations regarding economic policy. It is important to acknowledge, however, that this approach is not lacking potential drawbacks. By mandating explicit congressional authorization, the Court's decision could slow the government's ability to respond quickly to sudden economic crises or emerging threats. In emergency situations that demand rapid action, additional procedural steps may delay the implementation of needed economic measures. Policymakers will need to balance the constitutional imperative for legislative clarity with the practical necessity of swift executive responses, particularly in the face of surprising international developments.

Indeed, multiple existing trade laws already allow the President to impose tariffs under specific conditions.

The decision clarifies that IEEPA is not one of those statutes.

If the executive branch wishes to impose tariffs, it must rely on statutes that actually grant that power.

The Supreme Court’s ruling ultimately reinforces one of the most important structural principles in the American constitutional system: separation of powers.

The Constitution divides authority among three branches of government so that no single branch accumulates excessive power. When courts enforce these boundaries, they are not interfering with government policy—they are preserving the constitutional framework that protects liberty.

In this case, the Court reaffirmed that the power to tax—including the power to impose tariffs—belongs primarily to Congress. This approach conforms with course readings such as Epstein and Walker, Constitutional Law for a Changing America, which emphasize that Article I, Section 8, assigns the taxing power to the legislative branch as a core feature of the separation of powers. Additionally, in our reading of The Federalist Papers, Madison underscores that only a representative legislative body should control decisions involving the 'pockets of the people,' consequently supporting the Court's conclusion. Engaging these materials demonstrates that the Court's decision is not an isolated interpretation, but is rooted in foundational constitutional theory discussed in class.

Rather than expanding executive authority through ambiguous statutory language, the Court insisted on what the Constitution requires: clear authorization from the legislative branch before the executive branch exercises congressional powers.

Far from betraying the Constitution, the Court’s ruling strengthened it.