"The Supreme Court on Tuesday night rejected the Biden administration’s plea for a reprieve from a district-court order requiring it to reinstate a Trump-era program known as the 'remain in Mexico' policy..."

"... which requires asylum seekers to stay in Mexico while they wait for a hearing in U.S. immigration court.... The decision means that the Biden administration must resume enforcing the policy 'in good faith' while litigation continues in the lower courts.... [Texas and Missouri] contend that, without the policy, large numbers of migrants can enter the United States based on dubious asylum claims, imposing costs on the states....  The states rejected the administration’s argument that requiring it to reinstate the policy would lead to 'chaos at the border'... Indeed, the states noted, news reports have indicated that the Biden administration itself has 'privately discussed' reviving the policy because of the problems at the border.... In a brief unsigned order issued shortly before 8 p.m. on Tuesday night, the court explained that the Biden administration was not likely to succeed – one of the criteria for obtaining this kind of request for emergency relief – in showing that its decision to end the policy was not 'arbitrary and capricious' – that is, reasonable and reasonably explained. The order cited the court’s 2020 ruling in Department of Homeland Security v. Regents of the University of California, which rejected the Trump administration’s efforts to terminate the Deferred Action for Childhood Arrivals program, an Obama-era policy that protected people who were brought as children to the U.S. without authorization. In Regents, the court held that the Trump administration had not properly explained its decision to end DACA."

Writes Amy Howe at SCOTUSblog.