a federal judge on Friday ordered the Trump administration to immediately release Mahmoud Khalil, the former Columbia University graduate student activist who has been held in a Louisiana detention center since his arrest in early March. The judge had previously ruled that Khalil could not be held by U.S. Immigration and Customs Enforcement based on a vague federal statute focused on potential “adverse foreign policy consequences” of his presence in the country. The latest ruling rejected the government’s arguments that Khalil, who missed the birth of his son while in detention, posed a flight risk, much less a danger to...