The Supreme Court of the United States on Friday ruled 6–3 that President Donald Trump violated federal law by unilaterally imposing sweeping global tariffs under emergency powers, delivering a major setback to a policy central to his foreign and economic agenda.

Chief Justice John Roberts, writing for the majority, held that the president exceeded his authority under the International Emergency Economic Powers Act (IEEPA), a 1970s-era law that permits presidents to regulate certain economic transactions during national emergencies.

“The president asserts the extraordinary power to unilaterally impose tariffs of unlimited amount, duration, and scope,” Roberts wrote. “In light of the breadth, history, and constitutional context of that asserted authority, he must identify clear congressional authorization to exercise it.”

The court concluded that IEEPA does not explicitly grant the president the authority to impose tariffs. “When Congress grants the power to impose tariffs, it does so clearly and with careful constraints,” Roberts stated. “It did neither here.”

Justices Amy Coney Barrett and Neil Gorsuch joined Roberts and the court’s three liberal justices in the majority. Justices Clarence Thomas, Samuel Alito and Brett Kavanaugh dissented.

No Immediate Clarity on Refunds
While the court invalidated the tariffs, it did not specify what should happen to the more than $130 billion already collected. According to data from United States Customs and Border Protection, about $134 billion had been raised from over 301,000 importers as of mid-December.

The issue of whether importers will receive refunds is expected to be addressed by lower courts. In his dissent, Kavanaugh noted that the ruling offered “nothing today about whether, and if so how, the government should go about returning the billions of dollars that it has collected.”

Administration officials had warned that mass repayments could significantly disrupt the US economy.

A Major Legal Defeat
The case marks the first fully reviewed Trump-related dispute of his second term and represents his most significant loss at the Supreme Court, which had previously sided with his administration in several emergency rulings.

Legal analysts described the judgment as a strong assertion of judicial limits on executive power. The ruling centered on whether the IEEPA’s authority to “regulate” imports includes the power to impose tariffs. The majority rejected that interpretation.

“Taxes, to be sure, may accomplish regulatory ends,” Roberts wrote. “But it does not follow that the power to regulate something includes the power to tax it.”

Justice Elena Kagan, in a concurring opinion joined by the other liberal justices, said the decision could be reached through standard statutory interpretation without invoking the controversial “major questions doctrine,” which requires explicit congressional approval for actions of vast economic significance.

Political Reactions
Former Vice President Mike Pence praised the ruling, calling it “a victory for the American people and a win for the separation of powers.”

Republican lawmakers who had criticized the tariffs also welcomed the decision, arguing that Congress — not the president — holds constitutional authority over taxation.

Alternative Tariff Options Remain
Although the court struck down Trump’s use of IEEPA to impose the duties, other legal avenues remain available. Provisions within the Trade Act of 1974 and the Tariff Act of 1930 allow limited tariff increases under specific conditions, though with tighter constraints such as time limits and industry-specific investigations.

The decision stems from lawsuits filed by importers, including New York-based V.O.S. Selections and Illinois toy company Learning Resources, which argued that the administration’s interpretation of IEEPA amounted to an unconstitutional expansion of executive authority.

With the ruling, the Supreme Court reaffirmed that significant economic measures such as tariffs require clear authorization from Congress, reinforcing constitutional boundaries between the legislative and executive branches.