The Supreme Court of the United States delivered a significant ruling blocking President Donald Trump from using an emergency powers statute to impose sweeping tariffs on most U.S. trading partners without congressional approval. In a 6–3 decision, the Court held that Trump’s reliance on the International Emergency Economic Powers Act (IEEPA) to justify broad-based tariffs exceeded the authority granted to the executive branch under that law. The ruling represented a substantial setback for one of the president’s central economic strategies, which he had described as essential to protecting American industry and correcting longstanding trade imbalances. The decision reaffirmed the constitutional principle that the power to impose tariffs rests primarily with Congress, not the president, even when foreign affairs and economic pressures are at issue.

Writing for the majority, Chief Justice John Roberts emphasized that the Constitution explicitly assigns the authority to levy tariffs and regulate commerce with foreign nations to Congress. He stressed that the Framers of the Constitution vested this power in the legislative branch alone, notwithstanding the foreign policy dimensions that tariffs often carry. Roberts rejected the administration’s interpretation of IEEPA, which relied on the words “regulate” and “importation” to claim independent presidential authority to impose tariffs on imports from any country, at any rate, for any duration. According to Roberts, these isolated words could not reasonably be stretched to support such expansive authority. He argued that if Congress intended to delegate its tariff power so broadly, it would have done so clearly and with explicit limitations, rather than through vague statutory language. The Court concluded that IEEPA does not authorize the president to unilaterally impose wide-ranging tariffs in the absence of direct congressional consent.

The three dissenting justices—Brett Kavanaugh, Samuel Alito, and Clarence Thomas—disagreed with the majority’s interpretation. In a forceful dissent, Kavanaugh warned of significant practical consequences stemming from the Court’s ruling. He focused particularly on the potential financial fallout if the tariffs imposed under IEEPA are deemed unlawful. According to Kavanaugh, the United States could face the prospect of refunding billions of dollars to importers who had already paid the tariffs. He noted that many importers may have passed these costs on to consumers or business partners, complicating any reimbursement process. Kavanaugh characterized the likely refund proceedings as potentially chaotic and burdensome, describing the situation as a possible “mess.” Notably, the majority opinion did not directly address the question of refunds, leaving that issue to be resolved in lower courts.

Throughout the litigation, the Trump administration maintained that IEEPA grants the president authority to respond to “unusual and extraordinary threats” to the nation, particularly when a national emergency has been declared. Trump argued that deep and persistent trade deficits constituted such an emergency, asserting that decades of unfavorable trade balances harmed American workers and industries. The Department of Justice urged the Supreme Court to allow the tariffs to remain in place, contending that denying the president this authority would leave the United States vulnerable to foreign trade retaliation without effective tools for defense. Supporters of the administration’s position argued that the executive branch must retain flexibility to act swiftly in response to global economic challenges. Legal scholar Jonathan Turley of George Washington University observed that, despite the setback, the administration retains other statutory mechanisms for imposing tariffs, suggesting that the broader policy debate over executive trade powers is far from settled.

Opponents of the tariffs countered that no president in the roughly five decades since IEEPA’s enactment had used the law to impose tariffs. They argued that the statute was designed primarily to address specific economic sanctions and asset freezes during genuine emergencies, not to authorize comprehensive trade policy measures. The plaintiffs further contended that the trade deficits cited by Trump had persisted for nearly half a century, undermining the claim that they represented an “unusual and extraordinary” crisis warranting emergency action. Allowing the executive branch to impose universal tariffs under IEEPA, they warned, would dramatically expand presidential authority at the expense of Congress and upset the balance of powers carefully constructed by the Constitution. Lower courts agreed with this reasoning. The U.S. Court of International Trade unanimously blocked the tariffs, holding that the president does not possess “unbounded authority” under the emergency statute. The U.S. Court of Appeals for the Federal Circuit likewise rejected the administration’s interpretation of IEEPA.

Ultimately, the Supreme Court’s ruling reinforces a fundamental separation-of-powers principle: while the president plays a central role in foreign policy and national security, the authority to set tariffs remains primarily legislative. By limiting the scope of IEEPA, the Court signaled that emergency powers cannot be invoked to bypass Congress in matters of broad economic policy without clear statutory authorization. At the same time, the decision leaves open important practical and political questions. Lower courts must now determine how to handle potential refunds of previously collected tariffs, an issue that could carry substantial financial implications. Moreover, the administration may pursue alternative legal pathways to implement its trade agenda, meaning that the broader debate over executive authority in trade policy is likely to continue. The case stands as a landmark affirmation of congressional control over tariffs and a reminder that even in areas touching foreign affairs, presidential power is not unlimited.