A federal appeals court on Tuesday spent more than an hour grappling with whether President Donald Trump unlawfully federalized thousands of members of California’s National Guard to beef up security in Los Angeles amid unrest over immigration enforcement.

A federal judge has ruled that President Trump’s call-up of the California National Guard was illegal, prompting an immediate appeal from the Trump administration. The troops will remain in place for at least a few days after the 9th Circuit Court of Appeals granted an administrative stay of the judges ruling.