A wave of concern is sweeping through Republican ranks on Capitol Hill as the Department of Justice begins its investigation into Federal Reserve Chair Jerome Powell. This inquiry, centered on statements Powell made about the Fed's headquarters renovations, is igniting debates over the central bank's autonomy.

Powell disclosed on Sunday that the DOJ's investigation might be politically motivated, stemming from President Donald Trump’s displeasure with the Fed's reluctance to significantly lower interest rates. Despite criticisms from figures like Sen. Kevin Cramer (R-N.D.), who has questioned Powell's transparency with Congress, he stated, "I do not believe, however, he is a criminal," expressing a desire to swiftly conclude the investigation and restore confidence in the Fed.

The Senate Banking Committee, where Cramer is a member, is set to convene to discuss upcoming cryptocurrency legislation. However, insiders anticipate that the Powell probe will also be a topic of discussion. "There will be a lot of chatter," predicted one of the Republicans privy to the meeting plans.

Over in the House, the issue also resonates with Republicans such as Rep. Mike Lawler (R-N.Y.), who emphasized the importance of maintaining the Federal Reserve’s independence despite his reservations about Powell's handling of inflation and interest rates.

The probe has even impacted discussions around future Fed appointments. Sen. Thom Tillis (R-N.C.) declared his intent to block all Fed nominations until the investigation is resolved, highlighting the broader implications for the independence of both the Federal Reserve and the Department of Justice under scrutiny from the Trump administration.

The controversy traces back to a heated Senate hearing last June, fueled by a report on cost overruns during the Fed's renovations. Now, as the DOJ investigation unfolds, it threatens not only the leadership within the Fed but also the very principle of its independence, a cornerstone of its credibility and functionality in the U.S. financial system.