In a legal escalation that could have far-reaching impacts on the future of the Federal Reserve and the limits of executive power, President Donald Trump has asked the U.S. Supreme Court to let him fire Fed Governor Lisa Cook, whom he claims committed mortgage fraud.

In a 41-page court filing requesting a stay of a preliminary injunction barring Cook’s removal, Solicitor General D. John Sauer accuses lower courts of “improper judicial interference with the President’s removal authority,” arguing that “so long as the President identifies a cause, the determination of ‘some cause relating to the conduct, ability, fitness, or competence of the officer’ is within the President’s unreviewable discretion.”

Trump moved to fire Cook on Aug. 25. In a letter addressed to Cook shared on Trump’s personal Truth Social account, the president wrote that “I have determined that there is sufficient cause to remove you from your position.”

Trump’s basis for Cook’s removal was a criminal referral letter sent to Department of Justice officials on Aug. 15 by Bill Pulte, director of the Federal Housing Finance Agency. In that letter, Pulte alleged Cook fraudulently claimed homes in two states as her primary residence to potentially obtain more favorable mortgage terms, and then allegedly received rental income on one of the properties.

Sauer’s filing with the Supreme Court states: “The President’s strong concerns about the appearance of mortgage fraud, based on facially contradictory representations made to obtain mortgages by someone whose job is to set interest rates that affect Americans’ mortgages, satisfies any conception of cause.”

Due process and ‘for cause’ questions

A key question the Supreme Court will be asked to consider is whether Cook’s Fifth Amendment due process rights were violated.

In a Sept. 9 ruling granting a temporary restraining order that allowed Cook to remain in office, U.S. District Judge Jia Cobb noted that those procedural rights were likely violated when Trump announced on social media he was firing Cook, five days after Pulte publicly released the criminal referral letter on the social platform X.

“Was anything sent to her directly?” Cobb asked at a preliminary court hearing, according to CNN. “You still have to serve someone. You have to give them information.”

A federal appeals court upheld Cobb’s ruling on Sept. 15 in a 2-to-1 decision, with Circuit Judge Bradley Garcia writing in the majority opinion that Cook “may not be removed prior to being provided ‘some kind’ of meaningful notice and opportunity to respond.”

The appeals court ruling allowed Cook to attend the Fed’s Sept. 16-17 monetary policy meeting. The central bank’s rate-setting committee lowered interest rates by a quarter-point following that meeting, with Cook joining 10 voting members in approving the action. Recent Trump appointee Stephen Miran cast the lone dissenting vote, favoring a larger 0.5% rate cut.

The latest court filing by Trump’s legal representation claims “Cook cannot complain about sufficient process,” arguing the Fed governor had sufficient time to respond to the charges. “Due process is a flexible concept,” it states, adding that “whatever process is due to principal officers was provided here.”

The nation’s highest court will also be tasked with determining the legal ramifications of the term “for cause,” which isn’t defined in the Federal Reserve Act, the 1913 legislation that established the central bank.

The real estate transactions referenced in Pulte’s criminal referral letter occurred prior to Cook’s becoming a Fed governor. Cobb’s ruling stated that her reading of legal precedent is that a Fed governor’s removal would be limited to behavior that occurred while in office and “whether they have been faithfully and effectively executing their statutory duties.”

Sauer’s application to stay the lower court’s injunction claims “the phrase ‘for cause’ allows the President to remove an officer for any reason relating to the officer’s ‘conduct, ability, fitness, or competence.’” It adds, “The President’s application of that standard is not subject to judicial review.”

Cook’s attorneys are expected to swiftly file a response to Trump’s Supreme Court request.

In a Sept. 13 filing with the federal appeals court, Cook’s lawyers maintained that the “district court correctly concluded that pre-office conduct does not constitute cause,” while noting that “Governor Cook has never been found guilty of — or even been formally charged with — any wrongdoing.”

Cook’s legal team also referenced a Supreme Court ruling from May that called the Federal Reserve a “uniquely structured, quasi-private entity that follows in the distinct historical tradition of the First and Second Banks of the United States.” They argue that judicial characterization provides “statutory protection against the at-will removal of its members.”

“President Trump’s attempted removal of Governor Lisa Cook, if allowed, would mark an immediate end to that history,” Cook’s attorneys wrote, “and it would send a destabilizing signal to the financial markets that could not be easily undone.”