The court’s action appears to bar the administration from immediately resuming the flights that last month carried hundreds of migrants to a notorious prison in El Salvador. The flights came soon after President Donald Trump invoked the Alien Enemies Act for the first time since World War II to justify the deportations under a presidential proclamation calling the Tren de Aragua gang an invading force.

The majority said nothing about those flights, which took off without providing the hearing the justices now say is necessary.