The Supreme Court ruled Friday that President Donald Trump doesn’t have the tariff authority he claimed, in a decision authored by Chief Justice John Roberts.

The ruling addressed a key Trump policy as the high court considers the scope of presidential power across several cases this term. The court has broadly empowered the Republican president but has occasionally checked him, this being one of those occasions.

The justices agreed in September to consider the tariff issue on an expedited basis, granting review in two separate cases, both of which the administration lost in the lower courts. One of them came through a specialized trade and appeals court, and the other came through a general federal court in Washington.

When the high court heard oral arguments in November, the justices sounded skeptical of the administration’s position that Trump was authorized to impose the sweeping tariffs under a federal law called the International Emergency Economic Powers Act (IEEPA).

The president cited the law when he announced the so-called trafficking tariffs on products from Mexico, Canada and China due to what he said was their failure to stop fentanyl from coming to the United States. He also cited that law when he announced the so-called reciprocal tariffs on “all trading partners.”

Court rules against Trump 6-3

Roberts wrote Friday that Trump “asserts the independent power to impose tariffs on imports from any country, of any product, at any rate, for any amount of time.” But the chief justice wrote that the law Trump invoked to do so “cannot bear such weight.”

Roberts noted that no previous president had read the law to confer such power. “We claim no special competence in matters of economics or foreign affairs,” he wrote, adding: “We claim only, as we must, the limited role assigned to us by Article III of the Constitution. Fulfilling that role, we hold that IEEPA does not authorize the President to impose tariffs.”

Though Roberts led the court on the 6-3 bottom line rejecting Trump, the case prompted a web of separate opinions totaling nearly 170 pages, including Roberts’ opinion. Justice Brett Kavanaugh wrote a dissenting opinion joined by Justices Clarence Thomas and Samuel Alito, which argued that the law authorizes presidents to impose tariffs on foreign imports during declared national emergencies.

Kavanaugh’s dissent

Kavanaugh wrote that the immediate effect of the ruling could be “substantial” because the government “may be required to refund billions of dollars to importers who paid the IEEPA tariffs, even though some importers may have already passed on costs to consumers or others.” But the Trump appointee also wrote that the decision “might not substantially constrain a President’s ability to order tariffs going forward,” because, he wrote, “numerous other federal statutes authorize the President to impose tariffs and might justify most (if not all) of the tariffs at issue in this case—albeit perhaps with a few additional procedural steps that IEEPA, as an emergency statute, does not require.”

At the November hearing, Trump appointee Amy Coney Barrett questioned U.S. Solicitor General John Sauer on the worldwide tariffs. “And so is it your contention that every country needed to be tariffed because of threats to the defense and industrial base? I mean, Spain, France? I mean, I could see it with some countries, but explain to me why as many countries needed to be subject to the reciprocal tariff policy as are,” Barrett said. Sauer said “asymmetric treatment” from other countries “is a global problem.”

She and fellow Trump appointee Neil Gorsuch were part of the 6-3 majority, along with Roberts and the court’s three Democratic appointees, though those two sets of justices (Gorsuch/Barrett and Justices Sonia Sotomayor/Elena Kagan/Ketanji Brown Jackson) joined different parts of Roberts’ ruling on Friday due to their different interpretative methods.

In the case called Trump v. V.O.S. Selections, the Federal Circuit ruled that Trump overstepped his authority in attempting to rely on IEEPA. “The statute neither mentions tariffs (or any of its synonyms) nor has procedural safeguards that contain clear limits on the President’s power to impose tariffs,” the circuit court wrote in a divided ruling that split the court 7-4, though not strictly along the party lines of the presidents who appointed the judges.

In the other case, Learning Resources v. Trump, U.S. District Judge Rudolph Contreras, an Obama appointee, wrote that if Congress “had intended to delegate to the President the power of taxing ordinary commerce from any country at any rate for virtually any reason, it would have had to say so.” He wrote that no other president “has ever purported to impose tariffs under IEEPA.”

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