Every living former head of the Federal Reserve condemned an “unprecedented” attempt by the Trump administration to weaken the central bank’s independence, after the Department of Justice opened a criminal investigation into its chair, Jerome Powell.

Ex-Fed chairs Alan Greenspan, Ben Bernanke and Janet Yellen warned similar prosecutorial attacks in other countries had led to “highly negative consequences” for the cost of living – and argued they had “no place” in the US.

“The reported criminal inquiry into Federal Reserve Chair Jay Powell is an unprecedented attempt to use prosecutorial attacks to undermine that independence,” a blunt statement signed by 13 former senior officials 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 has no place in the United States whose greatest strength is the rule of law, which is at the foundation of our economic success.”

Late on Sunday, it emerged that the justice department had served the Fed with grand jury subpoenas on Friday, threatening a criminal indictment related to his testimony before the Senate banking committee in June last year, regarding renovations to the Fed’s historic office buildings in Washington DC.

In response, Powell argued he had been threatened with criminal charges because the Fed had set interest rates “based on our best assessment of what will serve the public, rather than following the preferences of the president”.

More details soon …