Campaigners led by Gina Miller are demanding the chancellor launch an independent review into Andrew Bailey’s appointment as Bank of England governor, saying the Financial Conduct Authority during his time as its chief executive was characterised by a “toxic cocktail of negligence, incompetence and indifference” that allowed a string of financial scandals to go unchecked.

The group has written to the chancellor, Rishi Sunak, and the head of the Treasury select committee, Conservative MP Mel Stride, saying Bailey must answer questions over scandals that wiped out the savings of small investors during his watch as the chief executive of the City regulator.

Miller, best known for her legal challenge over the government’s attempt to push through Brexit without parliamentary approval, said a report compiled by her True and Fair Campaign was a “damning dossier” on Bailey’s track record and raised questions over whether he was “a fit and proper person” to be the Bank’s next governor.

Among the alleged failures was the lack of investigation into allegations contained in Lloyds’ internal Turnbull report, in which a former employee claimed executives covered up fraud at the HBOS branch in Reading, and a lack of sufficient regulation around peer-to-peer platforms like Lendy which collapsed last year. Miller’s report also pointed to the collapse of London Capital & Finance and the liquidation of Neil Woodford’s once-popular flagship investment fund.

The government launched an an official inquiry into the City regulator’s role in the LC&F scandal in May 2019. That investigation is still ongoing.

Speaking at the launch of the report, Asleep at the Wheel, Miller said that while Bailey was in charge “the FCA has been characterised by a toxic cocktail of negligence, incompetence and indifference to the needs of ordinary depositors, investors and pensioners. On his watch, tens of thousands of Britons have lost money – in many cases losing their life savings which has devastated their lives, families and business.”

Miller said the campaign group - which she leads alongside her husband and City stockpicker, Alan Miller - will launch an online petition that will require parliament to consider a debate on Bailey’s appointment if it collects more than 100,000 signatures.

Bailey was appointed the next Bank of England governor by the former chancellor Sajid Javid in late December. He will take over from Mark Carney on 16 March.

The shadow chancellor, John McDonnell, has backed Miller’s report, saying Labour was right to call for a delay to Bailey’s appointment. “This report reinforces that we were right to call on the last chancellor on several occasions to postpone the installation of Andrew Bailey in office as governor until there had been an independent review of his role at the FCA,” he said.

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Miller said: “Were he [Bailey] to be confirmed in this highly responsible and prominent role, it would be a gross betrayal of the government’s duty to protect consumers and a textbook example of rewarding failure. But it also raises questions about the culture of the FCA under Mr Bailey.”

An FCA spokeswoman said the regulator rejected Miller’s claims, saying they contained a number of inaccuracies and were made “with little understanding of the role of the FCA”.

“We have disagreed with the Millers on numerous issues relating to the investment industry, and our oversight of it, over recent years and we note their previous calls on Andrew to resign. This is just another example.”

The spokeswoman added that the FCA’s interventions have benefitted millions of people, including the most vulnerable consumers, through price caps on payday loans, rent-to-own schemes and overdraft charges. “We hold firms to account and where we find failures we take action, with the FCA fining firms nearly £5bn since 2013 and tens of billions of pounds being returned to customers through redress schemes.”

The Treasury defended Bailey’s appointment, saying: “The country needs experienced, credible leadership in the role of governor and Andrew Bailey will deliver that. With nearly 40 years of experience in UK monetary and financial policy, his record speaks for itself.”

The Guardian contacted the Bank of England for comment.

