The case raises questions about the Trump administration's adherence to limits set by the Supreme Court. It carries the risk of a significant clash between the two coequal branches of government and potentially a full-blown constitutional crisis.

High court acted in an emergency appeal from the American Civil Liberties Union contending that immigration authorities appeared to be moving to restart removals under the Alien Enemies Act of 1798.

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