The ruling, which will almost certainly be appealed, is a blow to the Trump administration’s efforts to assert more control over the traditionally independent Fed, which sets short-term interest rates to achieve its congressionally mandated goals of stable prices and maximum employment. Congress has also sought to insulate the Fed from day-to-day politics.

Trump said he was firing Cook on Aug. 25 over allegations raised by one of his appointees that she committed mortgage fraud related to two properties she purchased in 2021, before she joined the Fed. Cook is accused of saying two properties were “primary residences,” which could have resulted in lower down payments and mortgage rates than if either was designated a second home or investment property.

Cook’s lawyers argued that firing her was unlawful because presidents can only fire Fed governors “for cause,” which has typically meant inefficiency, neglect of duty or malfeasance while in office. They also said she was entitled to a hearing and a chance to respond to the charges before being fired, but was not provided either. Her lawsuit denied the charges but did not provide more details.

The case could become a turning point for the 112-year-old Federal Reserv. Economists prefer independent central banks because they can do unpopular things like lifting interest rates to combat inflation more easily than elected officials.

Many economists worry that if the Fed falls under the control of the White House, it will keep its key interest rate lower than justified by economic fundamentals to satisfy Trump’s demands for cheaper borrowing. That could accelerate inflation and could also push up longer-term interest rates, such as those on mortgages and car loans. Investors may demand a higher yield to own bonds to offset greater inflation in the future, lifting borrowing costs for the U.S. government, and the entire economy.

If Trump can replace Cook, he may be able to gain a 4-3 majority on the Fed’s governing board. Trump appointed two board members during his first term and has nominated a key White House economic adviser, Stephen Miran, to replace Adriana Kugler, another Fed governor who stepped down unexpectedly Aug. 1. Trump has said he will only appoint people to the Fed who will support lower rates.

No president has sought to fire a Fed governor before.

The Supreme Court has signaled that the president can’t fire Fed officials over policy differences, but can do so “for cause,” typically meaning misconduct or neglect of duty. Cook has not been charged with any crime.

Trump has repeatedly attacked Fed Chair Jerome Powell and the other members of the Fed’s interest-rate setting committee for not cutting the short-term interest rate they control more quickly. It currently stands at 4.3%, after Fed policymakers reduced it by a full percentage point late last year. Trump has said he thinks it should be as low as 1.3%, a level that no Fed official and few economists support.

Powell recently signaled that the central bank was leaning toward cutting its rate at its next meeting Sept. 16-17. Still, it’s likely that the Fed will cut its key rate more slowly than Trump wants, and perhaps to as low as 3.25% or so — higher than Trump would prefer.

Cook is the first Black woman to serve as a governor. She was a Marshall Scholar and received degrees from Oxford University and Spelman College, and prior to joining the board she taught at Michigan State University and Harvard University’s Kennedy School of Government.