Trump's tariffs could be undone by one conservative doctrine: 'Life or death'

The high court is poised to rule soon on President Donald Trump’s use of an emergency wartime law to unilaterally impose sweeping tariffs on most U.S. countries.

Breanne Deppisch is a national politics reporter for Fox News Digital covering the Trump administration, with a focus on the Justice Department, FBI and other national news. She previously covered national politics at the Washington Examiner and The Washington Post, with additional bylines in Politico Magazine, the Colorado Gazette and others. You can send tips to Breanne at Breanne.Deppisch@fox.com, or follow her on X at @breanne_dep.

Plaintiffs told the court that Trump’s use of IEEPA to unilaterally impose his steep import duties violates the major questions doctrine, since IEEPA does not explicitly mention the word "tariffs." Rather, it authorizes the president to "regulate … importation" during a declared national emergency — plaintiffs noted, arguing that it falls short of the standard needed to pass muster for MQD.

"Congress does not (and could not) use such vague terminology to grant the executive virtually unconstrained taxing power of such staggering economic effect — literally trillions of dollars — shouldered by American businesses and consumers," they told the court in an earlier briefing.