Are Trump’s tariffs constitutional? The Supreme Court will decide

THE intersection of presidential power and congressional authority in the US is once again headed for the Supreme Court, this time through the unlikely vehicle of trade policy. The recent federal appeals court ruling striking down most of President Donald Trump’s tariffs represents more than a trade dispute; it raises a fundamental constitutional question about the limits of executive authority in economic policy.

At the centre of the controversy is Trump’s use of the International Emergency Economic Powers Act (IEEPA) to justify sweeping tariffs imposed in early 2025. These include the so-called “Liberation Day” tariffs announced in April, which imposed duties on imports from more than 60 countries, as well as tariffs on China, Mexico and Canada, ostensibly designed to combat fentanyl trafficking.

The federal appeals court’s recent 7-4 decision upheld a lower court ruling that these tariffs “exceed any authority granted to the president” under IEEPA.