Acting Solicitor General Sarah Harris argued in the court document that the lower court’s injunction harms President Donald Trump by diminishing his ability to manage the executive branch of his government.

“This Court should not allow lower courts to seize executive power by dictating to the President how long he must continue employing an agency head against his will,” Harris said.

Trump moved to fire Dellinger, a President Joe Biden appointee, on Feb. 7. Days later, on Feb. 10, the district court issued an administrative stay against the termination, which the court replaced with a temporary restraining order two days later.

On Saturday evening, a divided appeals court ruled in Dellinger’s favor.

Dellinger has fought against his ousting, describing his firing as unlawful.

According to federal law, the special counsel “may be removed by the President only for inefficiency, neglect of duty or malfeasance in office.”

Dellinger was appointed to the position for a five-year term by Biden last year.

According to its website, the Office of Special Counsel has the mission of protecting federal employees from illegal personnel practices, in particular, reprisal for whistleblowing.

Being head of the department means Dellinger has special authority to investigate actions taken by the Trump administration, which is seeking to eliminate potentially tens of thousands of federal jobs.

The Trump administration has already terminated thousands of federal positions, including both political appointees and civil servants. It has also received the resignations of more than 75,000 federal employees.

Criticism and lawsuits have been lobbed at the Trump administration over its seemingly arbitrary mass firings.

Veterans Affairs Secretary Doug Collins was named interim leader of the Office of Special Counsel as well as the Office of Government Ethics. David Huitema, head of the ethics watchdog, was relieved of his position, also on Feb. 7.