The U.S. Supreme Court recently ruled against former President Donald Trump's tariffs imposed under the International Emergency Economic Powers Act (IEEPA), with this significant decision including the support of several justices he appointed during his presidency. These justices, alongside three progressive members of the court, determined that only Congress has the authority to impose taxes or tariffs, thereby invalidating Trump's claims that his administration could act unilaterally. The ruling emphasized that tariffs have always been treated as a form of taxation under the U.S. Constitution, which stipulates that this authority lies solely with Congress.

The Court indicated that the IEEPA gives the president authority to regulate imports during a national emergency but does not explicitly grant the power to impose tariffs, a critical distinction that the justices highlighted in their ruling. Chief Justice John Roberts and two other conservative justices argued that such a substantial power should not be broadened through over-interpretation of vague legislative language, asserting that if Congress intended to bestow such significant powers upon the executive branch, it would have done so clearly.

In response to the ruling, Trump is pivoting to utilize another legal provision, invoking Section 122 of the Trade Act to propose a global tariff of 10%, which he later announced would increase to 15%. This provision allows for immediate action by the president in circumstances of severe trade deficits, yet it imposes a cap on the tariffs and requires congressional approval for any extension beyond 150 days. Trump's aggressive stance indicates he is not willing to relent in his trade policies even in the wake of a significant legal defeat.