As reported at NBC News, The SCOTUS justices did seem skeptical of the Tariff arguments and broad power of the President with regards to tariffs; although they did also grill the opposition council on licenses, license fees and the definition of the term "regulate."
The Trump administration argued that the president had the authority to issue sweeping tariffs under a law reserved for use during times of emergency.
The Supreme Court has a 6-3 conservative majority that has regularly backed Trump on various contentious cases since he took office in January, but based on the almost three-hour oral argument, the tariffs dispute could go the other way.
Both conservative and liberal justices asked tough questions of Trump's lawyer, Solicitor General D. John Sauer, though some of the conservatives seemed more sympathetic to his arguments.
The consequences are huge for Trump and the economy at large, with Americans increasingly anxious amid signs that the tariffs are contributing to, rather than alleviating, higher costs.
The legal question is whether a 1977 law called the International Emergency Economic Powers Act, or IEEPA, which allows the president to regulate imports when there is an emergency, extends to the power to impose global tariffs of unspecified duration and breadth.
The Constitution states that the power to set tariffs is assigned to Congress. IEEPA, which does not specifically mention tariffs, says the president can "regulate" imports and exports when he deems there to be an emergency, which occurs when there is an "unusual and extraordinary threat" to the nation.