Washington — Legal challenges to President Trump’s tariffs could put the president on a collision course with a Supreme Court that he shaped, as his use of emergency power to unilaterally impose the levies could run into legal doctrines championed by the conservative justices to limit executive authority.
Several things have to happen before the Supreme Court would consider the legality of Mr. Trump’s tariffs: the losing party in a lawsuit challenging his tariffs would have to appeal all the way up to the high court, and at least four justices would then have to agree to review the lower court’s decision. The high court would then have to decide the case on the merits, rather than a procedural issue.
But if that were to occur, the president could face skepticism from its six-member conservative wing — which includes three justices he appointed — as the cases raise doctrines that have been embraced by the conservative legal movement and invoked by the justices themselves in other cases: the major questions doctrine and nondelegation doctrine.
“If this issue gets to the Supreme Court, which is a big if, and if it comes down to the major questions doctrine or the nondelegation doctrine, and those are big ifs as well, we believe the court’s precedent requires them to rule in our favor,” said Ilya Somin, a law professor at George Mason University, who is involved in a lawsuit brought by the Liberty Justice Center on behalf of a group of small businesses in the U.S. Court of International Trade.
That suit is one of at least six court battles targeting Mr. Trump’s tariffs, which he has rolled out through a series of executive orders starting in February. The most sweeping tariffs were announced in April on what the White House has called “Liberation Day,” when the president imposed a 10% baseline tariff on nearly all U.S. trading partners and higher “reciprocal tariffs” on imports from 57 countries, which are now largely paused.
The tariffs have been in flux as the Trump administration has sought to engage in trade negotiations with countries to possibly lessen their burden.
Last week, Mr. Trump announced a framework for an agreement with the United Kingdom, which would leave in place 10% tariffs on imports from the country. Then, on Sunday, the White House said that the U.S. and China had agreed to a temporary easing of tariffs following negotiations between the two countries over the weekend.
The reductions would lessen the U.S. tariffs on Chinese imports to roughly 30%, while levies on American goods would drop to 10%.
While the president has said that there are more deals in the works, he hasn’t unveiled any additional agreements yet. Meanwhile, the lawsuits are moving forward. The U.S. Court of International Trade on Tuesday weighed a temporary bid to block the tariffs in one of the cases, which was the first major test of their legality.
The court battles may be brought by different parties, but several of them invoke the major questions and nondelegation doctrines in arguing that the tariffs cannot stand.
Major questions doctrine
Under the major questions doctrine, Congress must give clear authorization for a federal agency to decide an issue of major political or economic significance — a view that conservatives on the court have often cited in recent years to limit federal agency actions.
In the suit that Somin is involved in, the small businesses are challenging Mr. Trump’s authority to unilaterally impose tariffs under the International Emergency Economic Powers Act, or IEEPA. The plaintiffs argue that his attempt to use the law violates the major questions doctrine because Congress did not “speak clearly in granting such a broad and consequential power to upend the global economy.”
IEEPA makes no mention of the words tariffs or taxes, and no other president has used the law to impose levies on trading partners. The law gives the president the authority to impose economic sanctions, such as freezing foreign assets, after declaring a national emergency. Mr. Trump has declared that persistent trade deficits pose a national emergency and said the 10% baseline tariffs will remain in place until he determines that the threat posed by trade deficits is resolved.
In another lawsuit, led by the stationary company Simplified, lawyers with the New Civil Liberties Alliance argue that because Mr. Trump’s executive orders present a question of major political and economic significance, the major questions doctrine requires the president to show that IEEPA clearly gives him the power to impose tariffs. Mr. Trump, the suit alleges, cannot make that showing.
“Under the major questions doctrine, the court says that if Congress is going to delegate a significant power to the executive branch, we expect to see something pretty clear about it,” said Andrew Morris, one of the NCLA lawyers representing Simplified. “This is as big as it gets. This is restructuring the entire tariff framework for every country.”
Both the NCLA and the Liberty Justice Center are conservative-backed public interest law firms.
The Peterson Institute for International Economics, a research organization, estimated in February — after the president rolled out his first round of levies — that Mr. Trump’s tariffs on Canada, Mexico and China would cost the typical U.S. household more than $1,200 annually. The president’s 25% tariffs on most imports from Canada and Mexico, as well as a 10% increase in tariffs on products from China proposed by Mr. Trump at the time, mark the “largest tax increase in at least a generation,” the organization said in a report.
Separately, the Tax Foundation found that Mr. Trump’s current tariff regime will raise $2.1 trillion in revenue over the next 10 years and reduce U.S. gross domestic product by 0.7%.
That economic impact is at least as significant, and likely much larger, than actions that the Supreme Court has previously ruled were “major questions” that required a clear statement by Congress to authorize the executive action, the companies involved in the lawsuits say. Those efforts include former President Joe Biden’s attempt to cancel roughly $400 billion in student loan debt and a COVID-era vaccine mandate for companies with more than 100 employees, both of which were blocked by the Supreme Court.
“Here, we have an obvious major question in that this is the biggest trade war since the Great Depression. It makes previous cases look small by comparison,” Somin said. “To put it mildly, it is very far from clear that Congress delegated that kind of sweeping power to the president here.”
The Trump administration has argued in court filings that Congress, through IEEPA, delegated to the president the power to regulate importation through tariffs under specific circumstances. Justice Department lawyers have also said the major questions doctrine does not apply to presidential actions, especially those involving national security and foreign affairs.
Nondelegation doctrine
If a case involving Mr. Trump’s tariffs makes it to the Supreme Court and if the high court declines to apply the major questions doctrine, lawyers say the levies also violate the nondelegation doctrine, a long dormant legal concept rooted in the separation of powers.
Under that principle, Congress cannot delegate its legislative powers to executive branch agencies. The nondelegation doctrine was last invoked by the Supreme Court in two cases during the New Deal era, but some members of the Supreme Court have advocated for reviving it.
The high court has the chance to do that through a case challenging the constitutionality of a Federal Communications Commission’s mechanism for expanding phone and internet access to low-income and rural communities. But following oral arguments in March, the high court appeared skeptical of the effort to invalidate the fund.
In the tariff fights playing out in the courts, the plaintiffs argue that even if IEEPA granted the president broad, unlimited authority to issue tariffs worldwide, it would be an unconstitutional delegation of legislative authority. Congress has the power to tax and regulate commerce with foreign nations, and IEEPA does not have an “intelligible principle” that limits the president’s authority in slapping tariffs on imports, they say.
“If Congress passed this emergency statute that permits the president to rewrite tariff law from top to bottom and change it on a whim — set it at 10% across the board then 125% for China, then increase it, then pause it, then put it back in place — if Congress can give that to the president, there’s no limitation on the power passed along,” Morris said. “That’s a problem.”
Mr. Trump has notched some significant wins before the Supreme Court, and the court’s conservative 6-3 majority may be sympathetic to some of his assertions of executive power, such his firings of independent agency heads.
But the Supreme Court’s recent decisions — and writings from the justices — foreshadow that it could view his use of emergency power to unilaterally levy tariffs on goods from nearly every country as a step too far.
“One of the benefits of being a justice is you can reverse or ignore precedents,” Somin said, “but if you follow your own doctrines consistently, the outcome in this case should be pretty clear.”