The government of the previous President Donald Trump is petitioning the U.S. Supreme Court to allow his firing of Hampton Dellinger, the director of the Office of Special Counsel, an independent agency that protects government whistleblowers.

The Justice Department asked the court to overturn a Feb. 12 ruling by a federal judge that temporarily prohibited Trump from firing Dellinger. Acting Solicitor General Sarah Harris, in a filing obtained by Reuters, argued that the judge’s order was an “unprecedented assault on the separation of powers” and maintained lower courts have no right to prevent a president from firing the head of an agency.

Dellinger, appointed by former President Joe Biden, was set to serve until 2029. He sued the administration after being emailed on Feb. 7 that he was fired “effective immediately.” In his lawsuit, he alleges Trump exceeded his authority because federal law states that the Special Counsel can only be removed for “inefficiency, neglect of duty, or malfeasance in office.”

U.S. District Court judge Amy Berman Jackson in Washington, D.C., sided with Dellinger and temporarily reinstated him. In her view, Trump’s move to fire him without cause “plainly contravenes” the legal protection designed to ensure the independence of the Special Counsel.

The administration’s appeal was rejected on February 17 by the D.C. Circuit Court of Appeals, who believed that the case was premature as the judge’s order was interim.

Dellinger’s firing is part of a broader Trump agenda to reshape the federal government, eroding historic civil service protections by removing agency heads and staff. His case could establish a major precedent on how much control a president has to overhaul independent agencies.

The Office of Special Counsel is charged with the protection of whistleblowers, investigating allegations of government impropriety, and enforcing the Hatch Act, which forbids political activity on the part of federal employees.