Donald Trump’s tariffs could soon be toast

But Mr Trump’s position had a rough go in the nearly three-hour hearing. All three of the liberal justices expressed scepticism. Justice Ketanji Brown Jackson said that Congress enacted IEEPA “to constrain presidential authority” over trade policy, not to uncork it. Justice Sonia Sotomayor noted that the statute contains no reference to tariffs. Justice Elena Kagan surveyed the nine verbs in IEEPA that grant presidents emergency powers and concluded that the statute “just doesn’t have the one [power] you want”.

Three conservatives expressed doubts, too. Justice Amy Coney Barrett pressed Mr Sauer to name “any other time in history” when the salient phrase in IEEPA, allowing a president to “regulate…importation”, was understood to mean tariffs. John Roberts, the chief justice, referred to the court’s reluctance to bless consequential executive actions that have not been expressly authorised by Congress—an approach that doomed several of Joe Biden’s policies, including his plan to forgive student loans. The so-called major-questions doctrine, he said, “might be directly applicable” to Mr Trump’s claim under IEEPA. He added that it may be a stretch for a president to say the law lets him levy tariffs “on any product, from any country, in any amount, for any length of time”.

Justice Neil Gorsuch addressed Mr Sauer’s argument that the major-questions doctrine does not apply in the context of foreign affairs. Well, he said incredulously, “what would prohibit Congress from just abdicating all responsibility to regulate foreign commerce”, or its constitutional responsibility to declare war, to the president? Such a principle would mean “the gradual but continual accretion of power in the executive branch and away from the people’s elected representatives”.

Three justices—Samuel Alito, Brett Kavanaugh and Clarence Thomas—seemed keen to find a way to save Mr Trump’s tariffs. Justice Kavanaugh noted Richard Nixon’s invocation of an earlier law to impose a 10% tariff in 1971 and a 1976 decision upholding import fees. In colloquy with Neal Katyal, the lawyer representing businesses opposed to the tariffs, Justice Alito mused that not all tariffs are designed to raise revenue. In his closing, Mr Sauer built on Justice Alito’s notion that tariffs are not taxes but “leverage” to coerce trading partners “to change their behaviour”.

Before all the briefs were filed in Learning Resources, SCOTUSbot, our AI tool, predicted that Mr Trump’s tariffs would be upheld in nine of ten run-throughs. After reading all the filings, the bot switched to the challengers’ side in all ten simulations, but with rather low confidence. With the benefit of the oral-argument transcript, SCOTUSbot is even more persuaded that Mr Trump may have to rescind his tariffs and rejig them under different—and less expansive—legal authorities.