Justice Sonia Sotomayor penned a 17-page dissent joined in full by Justices Elena Kagan and Ketanji Brown Jackson and in part by Justice Amy Coney Barrett. She contended that her colleagues’ “decision to intervene in this litigation is as inexplicable as it is dangerous.”

Jackson wrote her own two-page dissent in which she lamented that the majority’s “fly-by-night approach to the work of the Supreme Court is not only misguided. It is also dangerous.”

The 1798 law at the center of the case is the Alien Enemies Act, which allows the president to detain or deport citizens of an enemy nation without a hearing or any other review by a court if either of two things occurs: Congress declares war, or there is an “invasion” or “predatory incursion.” The law has been invoked only three times – during the War of 1812, World War I, and World War II.