Trump increasingly has expressed agitation and anxiety about the looming decision in a case he says is one of the most important in U.S. history.
He has said it would be a “disaster” for the United States if the justices fail to overturn lower court rulings that found he went too far in using an emergency powers law to put his tariffs in place. Trump has suggested he may take the highly unusual step of attending the arguments in person.
The Justice Department, in its defense of the tariffs, has highlighted the expansive way Trump has used them, arguing that the trade penalties are part of his power over foreign affairs, an area where the courts should not second-guess the president.
Earlier this year, two lower courts and most judges on the U.S. Court of Appeals for the Federal Circuit found that Trump did not have power under the International Emergency Economic Powers Act, or IEEPA, to set tariffs – a power the Constitution grants to Congress. Some dissenting judges on the court, though, said the 1977 law allows the president to regulate imports during emergencies without specific limitations.
The courts left the tariffs in place while the Supreme Court considers the issue. Meanwhile, Trump has continued to wield them as he has tried to pressure or punish other countries on matters related – and unrelated — to trade.