How the Supreme Court May Rule on Trump’s Presidential Run

The Supreme Court, battered by ethics scandals, a dip in public confidence and questions about its legitimacy, may soon have to confront a case as consequential and bruising as Bush v. Gore, the 2000 decision that handed the presidency to George W. Bush.

Until 10 days ago, the justices had settled into a relatively routine term. Then the Colorado Supreme Court declared that former President Donald J. Trump was ineligible to hold office because he had engaged in an insurrection. On Thursday, relying on that court’s reasoning, an election official...