The U.S. Supreme Court raised doubts regarding President Donald Trump’s authority to impose sweeping tariffs using a decades-old emergency powers law.

The Use of IEEPA Questioned

During oral arguments on Wednesday, both Conservative and Liberal justices on the bench questioned Trump’s use of the International Emergency Economic Powers Act of 1977 to impose broad tariffs across all major U.S. trading partners.

The wording of the Act that was historically used to impose sanctions was questioned during the oral arguments, with Justice Amy Coney Barrett, a conservative judge appointed by Trump during his first term, asking whether it “has been used to confer tariff-imposing authority.”

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Liberal Justice Ketanji Brown Jackson said the statute was intended to constrain presidential authority, stating, “It's pretty clear that Congress was trying to constrain the emergency powers of the president.”

Appearing for the administration, U.S. Solicitor General D. John Sauer argued that Trump viewed the trade deficits as an economic and national security catastrophe, adding that they helped the country negotiate better trade deals in recent months.

Sauer said that unwinding these deals “would expose us to ruthless trade retaliation by far more aggressive countries and drive America from strength to failure with ruinous economic and national security consequences.”

The ‘Major Questions’ Doctrine

Conservative Chief Justice John Roberts suggested that the court could apply its “Major Questions” doctrine, which requires executive actions resulting in significant economic or political impact to be authorized by Congress.

Roberts added that the tariffs were an “imposition of taxes on Americans, and that has always been the core power of Congress.” He, however, acknowledged that the Court has long shown deference to the President when conducting foreign policy.

“Sure, the tariffs are a tax, and that’s a core power of Congress, but they are a foreign-facing tax, right? And foreign affairs is a core power of the executive,” he said.

Conservative Justice Brett Kavanaugh came out in support of the administration, noting that former President Richard Nixon had similarly imposed worldwide tariffs using the IEEPA’s predecessor statute in the 1970s, which he highlighted as a good precedent.

Neil Gorsuch, another conservative justice, disagreed with the foreign policy argument, suggesting that giving such sweeping authority to the President could undermine the separation of powers between the executive and legislative branches.

Trump Warns Ruling Could ‘Literally Destroy’ The US

Ahead of the hearing, Trump warned that the Court’s ruling against his tariffs could “literally destroy” the United States, arguing it would leave the country “struggling for years to come.”

His remarks underscored how central the tariffs and the legal authority behind them are to his administration's economic and foreign policy agenda.

Earlier this week, Trump had said that he wanted to attend the court’s hearing, but decided against it, saying, “It's not about me, it's about our country,” while again reiterating the importance of the tariffs for national security and addressing the nation’s persistent global trade imbalances.

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