The United States Supreme Court ruled that a large portion of the tariffs announced by Donald Trump in April 2025, in a decision handed down Friday by a majority of six judges to three. This highly anticipated ruling constitutes a major setback for the American administration, which had insistently defended this trade policy presented as one of the pillars of the president's second term.
These tariffs, described as "reciprocal" by Donald Trump, were imposed shortly after his return to the White House, relying on the International Emergency Economic Powers Act (IEEPA). This legislation is normally intended to define the president's powers in the event of a national emergency, particularly to block or regulate certain transactions involving foreign interests. The central question, therefore, was whether the IEEPA could serve as a legal basis for the imposition of widespread tariffs.
In its ruling, the Supreme Court held that the president could not justify the tariffs in the name of an economic emergency. The justices emphasized that the White House interpreted the IEEPA as granting the president unilateral and potentially unlimited tariff-related power, which would constitute a "major expansion" of presidential authority. The high court thus upheld the decisions of the lower courts.
The ruling concerns so-called "reciprocal" tariffs, but does not call into question those applied to specific sectors, such as automobiles, steel, or aluminum, which are based on different legal grounds. A crucial question now remains: that of potential refunds. According to an estimate cited in the press, the surtaxes collected could exceed $175 billion, which opens the door to a series of legal proceedings and a period of uncertainty for importers.
The decision could also reshuffle the diplomatic landscape. Several countries had negotiated under the threat of punitive tariffs of up to 50% and will now question the validity of the agreements reached with Washington. The European Union indicated that it was analyzing the ruling "carefully," reiterating the importance of stability and predictability in transatlantic trade relations.
Financial markets reacted positively: on Wall Street, the main indices returned to positive territory, while European markets also advanced. In Paris, the CAC 40 crossed the symbolic 8,500-point threshold for the first time, driven by stocks heavily exposed to exports to the United States. Donald Trump did not react immediately, but this ruling marks a major political turning point just months before the midterm elections scheduled for the end of the year.
