A chorus of previous Federal Reserve chairs, Treasury secretaries and prominent economists came together Monday to support Jerome Powell as the central bank leader faces potential perjury allegations from the Justice Department.

“The reported criminal inquiry into Federal Reserve Chair Jay Powell is an unprecedented attempt to use prosecutorial attacks to undermine that independence,” a statement backed by more than a dozen signatories said.

“This is how monetary policy is made in emerging markets with weak institutions, with highly negative consequences for inflation and the functioning of their economies more broadly,” it continued. “It has no place in the United States whose greatest strength is the rule of law, which is at the foundation of our economic success.”

Among the signers of the statement were former Fed Chairs Ben Bernanke, Janet Yellen and Alan Greenspan among with former Treasury Secretaries Henry Paulson, Timothy Geithner, Robert Rubin and Jacob Lew. Economists such as Glenn Hubbard, Kenneth Rogoff and Jared Bernstein also signed on.

Powell on Sunday confirmed that he’d been notified from the U.S. Attorney’s Office in Washington, D.C. that he is the subject of a probe into statements he made to Congress last June. In testimony on Capitol Hill, Powell answered questions regarding the massive renovation project at the central bank’s headquarters in the nation’s capital.