Trade and legal experts see up to 80% odds that the Supreme Court will rule against Trump’s global tariffs

The bank hosted a conference in London last month, and in a note on Monday it summarized highlights from a session on Trump’s trade policies.

Trade and legal experts said the odds that the high court will rule against the Trump administration are 70%-80% and expect a decision by the end of the year, according to the note, which added that the justices may not follow traditional ideological divides.

“While the sitting three liberal justices are expected to oppose IEEPA tariffs, Chief Justice Roberts and Justice Barrett—both with pro-business leanings—may also side against,” it said. “Kavanaugh is considered the swing vote and has voted with the majority 90% of the time. Legal experts point out that none of Trump’s three appointed justices is distinctively ‘Trumpy,’ and they have been less predictable than Republicans had hoped.”

Trump cited IEEPA when he imposed tariffs related to the fentanyl trade as well as his so-called reciprocal tariffs on U.S. trade partners around the world. But since then, a federal district court, the Court of International Trade, and a federal appeals court have said the tariffs are unconstitutional.

In the latest decision in August, the U.S. Court of Appeals for the Federal Circuit said its ruling won’t take effect until Oct. 14 to give the Trump administration time to appeal to the Supreme Court.

The court rulings represented severe blows to Trump’s trade policy as more than 80% of the tariffs he has announced so far in his second term were based on IEEPA.

The reciprocal tariffs also helped leverage a series of trade deals. That includes an agreement with the European Union, which pledged to invest $600 billion in the U.S. and buy $750 billion worth of U.S. energy products, with “vast amounts” of American weapons in the mix. Similarly, the U.S.-Japan trade deal entails $550 billion in investments from Tokyo.

While Trump’s other tariffs on various sectors like steel, aluminum and autos rely on a separate law and aren’t affected by the court rulings, a final defeat at the Supreme Court would mean the administration would have to pay back a big chunk of the $165 billion in tariff revenue it collected in the fiscal year through August. Trump’s overall tariff regime was expected to generate $300 billion-$400 billion on an annual basis, helping ease the bond market’s concerns about the U.S. budget deficit.

But even if the high court goes against Trump’s tariffs, that won’t put an end to his trade war as numerous other legal avenues are available to levy duties.

In fact, the administration has been rolling out other so-called sectoral tariffs in recent weeks, including on lumber and furniture.

But the alternate tariff routes don’t provide the same speed, scale or flexibility of IEEPA and would not fully recover the revenue lost, JPMorgan added.

“The potential loss of IEEPA tariffs does not end the tariff story, but fragments it,” the note said. “With more than 80% of announced tariffs relying on IEEPA, the administration would be forced to turn to narrower, more contested measures.”

But in a note last month, Capital Alpha’s James Lucier said there’s a “silver lining” in the federal appeals court’s 7-4 decision that struck down the IEEPA tariffs, pointing to a powerful argument from one of the dissenting judges.

Federal Circuit Judge Richard Taranto​made found that there are no limits the president’s ability to invoke tariffs by declaring an emergency under IEEPA.

“The dissenting opinion has opened a pathway by which informed legal commentators have assessed that the president now has a plausible pathway to a victory at the Supreme Court, despite his previous losses,” Lucier observed.