Prediction markets are losing confidence that the U.S. Supreme Court will uphold President Donald Trump’s broad tariff powers. Traders on both regulated and on-chain platforms have sharply reduced their exposure following this week’s court developments.
Data from Kalshi, a U.S.-regulated event market, showed Thursday that participants now see only a 29% chance the Court will side with Trump — a steep 28-point drop in a single day.
Over on Polymarket, Kalshi’s crypto-native rival where trades settle in USDC, odds fell even further to 25%, mirroring the same decline in sentiment.
Combined trading volume across both platforms has exceeded $1.3 million, underscoring how prediction markets are becoming an early barometer for shifts in political and judicial expectations.
Traders Now Expect Supreme Court to Rein in Trump’s Tariff Powers
Volatility has surged across prediction markets since the Supreme Court agreed to review the case in September, but Wednesday marked the sharpest single-day drop in odds since trading began.
The latest price action suggests that traders increasingly believe the Court will narrow the president’s authority to impose tariffs under emergency-powers statutes — a ruling that could significantly reshape how future administrations wield trade and fiscal tools.
The close alignment between Kalshi and Polymarket odds underscores a growing convergence between traditional and decentralized prediction markets, as both fiat and blockchain-based traders now interpret political and legal risk through similar frameworks of liquidity and probability.
Supreme Court Justices Cast Doubt on Trump’s Tariff Authority
Market jitters deepened after reports that several conservative Supreme Court justices appeared skeptical of former President Donald Trump’s claim to impose sweeping tariffs under emergency powers.
During Wednesday’s marathon session, the Court heard oral arguments in a case that could redefine the balance of power between the White House and Congress. At issue is whether the president can invoke the 1977 International Emergency Economic Powers Act (IEEPA) to levy import duties without congressional approval.
According to the Associated Press, even Trump-appointed justices raised concerns about the potential erosion of separation of powers and the dangers of concentrating fiscal authority within the executive branch.
Chief Justice John Roberts stressed that tariffs have long been a congressional prerogative, equating them to taxes. Justice Amy Coney Barrett questioned the rationale for targeting allies like Spain and France, while Justice Neil Gorsuch warned that granting such discretion could create a “one-way ratchet” toward unchecked presidential power.
Trump’s trade agenda has historically rippled through crypto markets — past tariff announcements stoked inflation fears and pushed Bitcoin higher as a hedge against economic instability. Yet at times, escalating trade tensions also triggered risk-off moves, prompting investors to pull back from crypto and shift into safer assets.
