The case, Trump v. Cook, stems from the president's attempt to halt a lower court ruling reinstating Cook after he fired her last year over alleged mortgage fraud. 

During oral arguments, multiple justices seemed skeptical of US Solicitor General D. John Sauer's arguments about the limits of judges' abilities to interfere with the president's power to fire Cook - with some raising questions about whether granting Trump's request would impact the public. 

Trump appointee Justice Brett Kavanaugh was among the skeptics, saying that Trump's position would "weaken if not shatter the independence of the Federal Reserve," while Amy Coney Barrett asked whether the risk to financial markets warranted "caution on our part," though she also suggested she wasn't ready to fully embrace Cook's position.

The Supreme Court on Wednesday is expected to review the legality of President Donald Trump's firing of Fed Governor Lisa Cook last August over allegations of mortgage fraud.

In a letter to Cook, Trump cited a provision of the Federal Reserve act of 1913 which allows a president to fire members "for cause." 

Cook challenged the firing, and after a lower court reinstated her, Trump asked the Supreme Court to intervene. During today's oral arguments, the justices are expected to probe several legal issues - including whether the mortgage allegations constitute the sort of cause that allows firings under the Federal Reserve Act. 

Of note, Federal Reserve Chair Jerome Powell is planning to attend - which US Treasury Secretary Scott Bessent on Tuesday said would be a mistake. 

Powell's plan to ?attend the court's oral arguments is a potent symbol of the administration's ongoing clash with the Fed following U.S. Department of Justice threats to pursue a criminal investigation of him. Powell called the threat a "pretext" to pressure ‍him over monetary policy. -Reuters

"I actually think that's a mistake," Bessent told CNBC. "If you're trying not to politicize the Fed, for the Fed chair to be sitting there, trying to put his thumb on the ?scale, is a real mistake."