More: Trump's attempt to remove a sitting Fed governor is unprecedented " and almost certainly illegal, according to legal scholars. Governors are appointed to 14-year terms and can only be fired "for cause," such as misconduct or failure to perform official duties. Personal financial claims " especially from before the appointment " don't meet that bar.

"This is a procedurally invalid removal under the statute," said Columbia law professor Lev Menand. "This is not someone convicted of a crime. This is not someone who is not carrying out their duties."

Cook, who was appointed by President Joe Biden in 2022, is the first Black woman to serve on the Fed's Board of Governors. She's now fighting back with a legal team led by high-powered attorney Abbe Lowell.

"His reflex to bully is flawed and his demands lack any proper process, basis or legal authority," Lowell said of Trump. "We will take whatever actions are needed to prevent his attempted illegal action."