Roberts’ decision came in response to a request filed by 19 Republican-led states, to reverse a lower court’s ruling that required the Joe Biden administration to lift the implementation of Title 42 by Wednesday, Dec. 21.

Texas Republican Governor Greg Abbott warned Sunday that, should the policy be lifted, his state would face “total chaos,” a sentiment echoed by other conservative border state leaders.

Title 42 permits U.S. Customs and Border Protection agents to expel undocumented migrants back to Mexico or to their home countries without review in order to prevent the spread of covid-19 in holding facilities.

In April, Biden announced that he intended to suspend the policy, leading to a humanitarian crisis along the U.S.-Mexico border.