In a case involving changes to birthright citizenship, the justices heard arguments on whether a single federal judge in a single district can block Trump administration policy across the country.

The Justices on the Supreme Court wrestled on Thursday with a high-stakes case involving birthright citizenship that’s poised to shape both the Trump Administration’s immigration policy and its attempts to expand presidential power.

It’s the second time the administration has sought emergency intervention from the high court in its bid to downsize the federal bureaucracy.