The Supreme Court ruled 6-3 that President Trump exceeded his authority when he imposed tariffs using a law reserved for national emergencies. Chief Justice John Roberts authored the majority opinion, and Justices Clarence Thomas, Samuel Alito, and Brett Kavanaugh dissented. This case made it to the high court after Mr. Trump appealed lower court decisions that ruled against his tariffs, which were issued through executive orders on several countries. The president invoked the International Emergency Economic Powers Act (IEEPA) to justify the tariffs, citing trade deficits and fentanyl trafficking as national emergencies. Private companies and various states sued, arguing that the president lacked constitutional and statutory authority to impose them. During argument, justices questioned attorneys about the separation of powers doctrine, if the word "regulate" in IEEPA authorizes the president to impose tariffs, and executive authority in declaring emergencies.