The U.S. Supreme Court on Wednesday faced a specific question of presidential power as justices from across the ideological spectrum challenged the legality of President Donald Trump’s sweeping tariffs, a policy that has reshaped global trade and tested the limits of executive power.
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The Public Defender confronted Dr. John Sawyer, who represents the Trump administration, sharply questions whether Trump has overstepped his authority by invoking a 1977 emergency law to impose sweeping tariffs on nearly every U.S. trading partner. Both conservative and liberal justices seemed skeptical that the law — the International Emergency Economic Powers Act (IEEPA) — gives the president such broad economic control.
At issue is whether Trump’s use of international law’s emergency powers to justify tariffs of unlimited scope and duration amounts to an unconstitutional overreach of Congress’s basic powers to tax and regulate trade. Lower courts have previously ruled against the administration, concluding that Trump’s expanded interpretation of the law violates the letter and intent of the law.
Executive power under the microscope
Chief Justice John Roberts questioned whether Trump’s tariff regime infringed on Congress’s authority, noting that “taxing Americans has always been Congress’ primary power.” Likewise, Justice Amy Coney Barrett pressed Sawyer on whether the phrase “import regulation” in IEEPA had historically been used to justify the imposition of tariffs.
Justice Elena Kagan stressed that the power to tax and regulate commerce “has always been essentially legislative,” while Justice Ketanji Brown Jackson argued that Congress’ purpose in passing the ERA was “to limit presidential power, not to expand it.”
Even conservative Justice Neil Gorsuch expressed concern that allowing Trump’s interpretation might lead to “a one-way escalation toward the continued accumulation of power in the executive branch.”
The doctrine of the great questions
The court’s deliberations also centered on the “Great Questions Doctrine,” which requires that any executive action that has a significant economic or political impact receive explicit authorization from Congress. Sawyer argued that this principle did not apply in the field of foreign affairs, but Roberts countered that the domestic tax implications of tariffs placed them squarely within the purview of Congress.
Neil Katyal, who represents a coalition of companies objecting to the tariffs, said it was “unconscionable” that Congress intends to give the president “the authority to reform the entire tariff system and the American economy in the process.”
Billions at stake, trade war in motion
Since their imposition, IEEPA-based tariffs have generated an estimated $1 89 billion dollars in revenue, according to U.S. Customs and Border Protection data. The administration insists that even if the Supreme Court overturns Trump’s use of IEEPA, the tariffs would still apply under other legal authorities.
The risks extend beyond local law. Trump’s aggressive use of tariffs has ignited a global trade war, rattled financial markets, alienated US allies, and injected volatility into global supply chains. The former president used tariffs as leverage in trade negotiations and as punishment for political disputes — targeting countries from China to Canada and India.
Historically, IEEPA has been used to freeze foreign assets or impose sanctions on hostile governments, not to tax imports. Critics warn that Trump’s approach, if upheld, could turn the emergency powers law into a tool for unilateral economic policymaking.
Specific constitutional test
The Supreme Court’s final ruling will have sweeping implications for the balance of power between Congress and the presidency – and for the stability of global trade.
With a conservative 6-3 majority, the court in recent months has sided with Trump on several emergency cases, allowing controversial policies to move forward while legal challenges continue. However, the intensity of questioning on Wednesday indicates unease about expanding executive power further.
A decision is expected in the coming months, although the administration has asked the court to move quickly given the economic risks.
If the justices side with Trump, future presidents could gain almost unlimited control over trade policy through emergency declarations, potentially reshaping American economic governance for decades to come.
