A US Trader’s Guide to the Supreme Court’s Looming Tariff Ruling

An upcoming Supreme Court ruling on the legality of the sweeping tariffs that President Donald Trump rolled out in April, briefly sending shockwaves through markets, looms as one of the next big tests for US stocks and bonds.

The equity market has extended its rise into the new year, with the S&P 500 Index hovering near a record. The advance, which has left the benchmark about 40% above its April lows, has been fanned by the artificial-intelligence boom and Trump’s decision to dial back some of his most draconian tariffs. Treasury yields have also come down from their mid-2025 peaks as traders bet the Federal Reserve will keep cutting rates while the economy cools.