The US Supreme Court has struck down President Donald Trump’s “global tariffs.” In a 6–3 ruling, the Court held that the International Emergency Economic Powers Act (IEEPA) does not give the President power to impose tariffs.
Chief Justice John Roberts announced the judgment and wrote the main opinion. Justices Clarence Thomas, Samuel Alito, and Brett Kavanaugh dissented.
Background to the dispute
The case began after President Trump declared national emergencies. He cited two concerns. First, he pointed to the influx of illegal drugs. Second, he raised concerns about long-standing trade deficits.
Next, the administration relied on IEEPA to impose tariffs. It set a 25% duty on most imports from Canada and Mexico. It also imposed a 10% duty on many imports from China.
Later, it introduced broader “reciprocal” tariffs. These started at 10% on imports from almost all trading partners. Over time, some tariffs on Chinese goods rose sharply. In some instances, they reached effective rates of 145%.
As a result, legal challenges followed. Small businesses filed separate suits. A coalition of states also challenged the measures.
The US Court of International Trade ruled against the government on summary judgment. After that, the US Court of Appeals for the Federal Circuit, sitting en banc, largely upheld the decision. The Supreme Court then heard the consolidated cases.
Majority’s reasoning
The majority grounded its ruling in Article I of the US Constitution. Article I gives Congress the power to “lay and collect Taxes, Duties, Imposts and Excises.” The Court treated tariffs as a form of taxation. Therefore, it said Congress holds primary authority over tariff-setting.
Because of that, the President must point to clear congressional approval before imposing tariffs.
The Court also applied the major questions doctrine. Under this approach, major economic and political actions require unmistakable statutory authorization. The majority said these tariffs carried vast national consequences. So, it demanded clear language from Congress.
However, the Court rejected the government’s reading of IEEPA. The government argued that IEEPA allows the President to “regulate … importation,” and that this includes tariffs. The majority disagreed. It said that phrase does not authorize tariffs of effectively unlimited scope, duration, or magnitude. It also noted that the tariffs depended mainly on a presidential emergency declaration.
In addition, the Court refused to expand IEEPA just because the issue involved foreign affairs or emergencies. It stressed that the Constitution still places tariff power with Congress, even when international trade is involved.
The dissents
Justice Brett Kavanaugh wrote the principal dissent. Justices Clarence Thomas and Samuel Alito joined him. Justice Thomas also filed a separate dissent.
The dissenters took a broader view of IEEPA. They argued that “regulate … importation” naturally includes tariffs. In their view, tariffs serve as a long-used tool to regulate foreign commerce.
They also criticized the majority’s framing. According to the dissent, the Court treated taxation and regulation as fully separate. The dissent said the statute does not require that strict divide.
Justice Kavanaugh further attacked the use of the major questions doctrine. He said IEEPA was meant to give the President flexibility during foreign threats and economic emergencies. He warned that the ruling could slow executive action in crises.
Justice Thomas raised a separate concern. He questioned the scope and legitimacy of the major questions doctrine itself. He also suggested that Congress may delegate significant authority to the President without the high level of clarity the majority demanded.
