More than 700 Post Office managers were convicted after faulty accounting software made it look as though money was missing from their sites.

Many of them were jailed, lost their livelihoods and reputations, and some even took their own lives.

The inquiry aims to establish the extent of the Post Office’s failures and accountability, and to provide recommendations for the future.

The affair has been described by the Criminal Cases Review Commission as “the most widespread miscarriage of justice ever seen, external and represents the biggest single series of wrongful convictions in British legal history”.

Ms Knight, who was cleared of false accounting in 2013, said that she had felt isolated and hopeless.

“Alan Bates, bless him, believed in truth and he wasn’t going to let it go.

“Our hero Alan was making a lot of waves parallel to when I was going through the courts,” she said.

“Honestly hand on heart, I owe that man my life because I don’t think if not for them making waves, I would have a criminal conviction.”