The justices' order, over a dissenting vote by Justice Sonia Sotomayor, overturns a lower court order that would have blocked the policy, at least for people arriving at the border crossings in Arizona and California. The lower court order was to have taken effect on Thursday. Instead, the “Remain in Mexico" policy will remain in force while a lawsuit challenging it plays out in the courts, probably at least through the end of President Donald Trump's term in January.