On Nov. 5, a skeptical U.S. Supreme Court heard oral arguments in two cases challenging President Trump’s authority to impose global tariffs.

For nearly three hours, the nine justices – and three lawyers – debated whether Trump overstepped his authority when he imposed sweeping global tariffs, ostensibly to tackle “national emergencies” tied to trade deficits and illegal fentanyl imports.

Justices from across the ideological spectrum expressed doubts that Trump’s tariffs are authorized under the 1977 International Emergency Economic Powers Act that gives the president the power to “regulate” imports.

Four of the justices – including one of Trump’s own appointees – expressed outright hostility to the administration’s position. At least two others took a more measured tone but voiced misgivings about the tariffs and seemed likely to rule against them.

Two justices asked pointed questions of both sides and were difficult to assess. Only Justice Samuel Alito appeared clearly receptive to upholding the tariffs.

Chief Justice John Roberts noted the extraordinary broad scope of Trump’s tariffs, suggesting that such a momentous policy needed express authorization from Congress.

That idea – that big policies from the executive branch must be tied to clear statutory language – is the “major questions doctrine.” Roberts invoked that doctrine during the Biden administration in rulings that struck down a student loan forgiveness plan and a climate change initiative.

Roberts suggested a “misfit” between the sweeping tariff authority Trump has claimed and the vague language in IEEPA. The statute is “being used for a power to impose tariffs from any country in any amount for any length of time,” he said.

Solicitor General John Sauer took heat from all sides when he pressed the administration’s argument.

Tariffs are taxes, most justices agreed, and many were dubious that Congress would casually surrender to the executive its core constitutional power.

Article I, Section 8, expressly grants Congress the “power to lay and collect taxes, duties, imposts and excises…” and “To regulate commerce with foreign nations…”

Once granted to Trump, any future president could then deploy tariffs to pursue their favored policy, several justices observed.

Demonstrating the scope of Trump’s claim, Justice Neil Gorsuch offered an example anathema to the current administration: “Could the president impose a 50% tariff on gas-powered cars and auto parts to deal with the ‘unusual and extraordinary threat’ from abroad of climate change?” he asked, citing language from IEEPA.

Sauer conceded that another president could use the same power for such purposes.

Gorsuch, a Trump appointee, aggressively grilled Sauer about the Constitution’s separation of powers. He noted emphatically that the power to tax – and therefor to tariff – belongs to Congress, not the president.

Justice Amy Coney Barrett, another Trump appointee, voiced skepticism that the trade deficit was a “national emergency” justifying the worldwide “across the board” tariffs that Trump has imposed.

Barrett also was dubious about Trump’s interpretation of IEEPA. Though that law allows “regulation” of imports, it never mentions the “T-word,” Barrett noted.

All three of the court’s liberal justices telegraphed they are likely to rule against Trump. Justice Sonia Sotomayor led and was joined by Justices Elena Kagan and Ketanji Brown Jackson.

Justice Brett Kavanaugh critically questioned both sides’ positions, leaving his ultimate decision uncertain. Justice Clarence Thomas’ questioning did not tip his hand.

Alito was the only justice whose questions suggested he would side with Trump.

Even if the court strikes down Trump’s “emergency” tariffs, the justices gave little indication how they might unwind the president’s signature economic policy and favorite diplomatic tool. Would previously paid duties be refunded? Would Congress be invited to step in, by ratifying the levies retroactively?

“It seems to me like it could be a mess,” Barrett observed.

Through September, the U.S. has collected $90 billion from these “emergency” tariffs.

It’s unclear when the court will rule. A decision may come before year-end.

E-mail Jim Hartman at [email protected].