Less than two weeks after the Supreme Court allowed President Donald Trump to use a controversial 18th century wartime authority to speed deportations, the issue has rocketed back to the justices in a second short-fuse appeal with enormous potential consequences.

Elected last year on a promise to crack down on migrants, Trump invoked the 1798 Alien Enemies Act in an attempt to swiftly deport accused members of Tren de Aragua, a criminal gang originating from Venezuelan prisons that his administration labels a terrorist group.

The early-morning order temporarily blocks the administration’s attempt to remove a group of Venezuelan migrants using the Alien Enemies Act.