A draft report has revealed the Post Office was aware of evidence that losses could be due to errors in the Horizon IT system but still pressed ahead with the Bates v Post Office Ltd case.
Campaigner Alan Bates led a group of 555 subpostmasters who took the Post Office to the High Court over the scandal, which was settled in December 2019.
Details of the document, first reported by the BBC, show “Post Office management” knew sub-postmasters may not be to blame for data discrepancies but continued to fight them in court regardless.
The draft report, called Bramble, was commissioned by the Post Office in March 2016 and carried out by consultancy firm Deloitte.
In the report, the firm said it had discussed its findings with “Post Office management”.
Errors in the Horizon IT system or remote tampering could have been responsible for losses discovered at branches, the report said.
Mr Bates’ story recently became the subject of an ITV drama titled Mr Bates vs The Post Office, starring actor Toby Jones.
At a secretly recorded Post Office meeting in July 2013, attended remotely by then chief executive Paula Vennells, management heard subpostmasters’ Horizon computers could be accessed remotely.
In 2015, Ms Vennells told MPs she was not aware of any miscarriage of justice.
The former chief executive ran the Post Office while it routinely denied there was a problem with its Horizon IT system, and wrongfully prosecuted hundreds of subpostmasters.
During the recording, obtained and aired by ITV News, investigators tasked by the Post Office with looking into possible issues with the system told her explicitly about allegations that accounts could be accessed remotely.
The Post Office continued to deny remote access was possible until 2019.
A Post Office spokesperson said: “The statutory public inquiry, chaired by a judge with the power to question witnesses under oath, is the best forum to examine the issues raised by this evidence.
“We continue to remain fully focused on supporting the inquiry get to the truth of what happened and accountability for that.”
The latest development comes after a senior MP called for police to investigate a series of covert recordings from 2013 which include Post Office executives discussing the Horizon IT scandal.
Liam Byrne, chairman of the Commons Business and Trade Committee, said the recordings were “the first evidence that people knew there was a problem”.
The recordings, uncovered on Wednesday by Channel 4 News, contained conversations between Post Office executives and two forensic accountants on May 22 2013.
These conversations – which included Post Office company secretary Alwen Lyons and Post Office chief lawyer Susan Crichton – suggest they knew there was an issue with the company’s Fujitsu IT system two years before the last sub-postmasters were jailed, in 2015.
Hundreds of subpostmasters were wrongly convicted of stealing after the Post Office’s defective Horizon accounting system made it appear as though money was missing at their branches.
The Post Office also forced at least 4,000 branch managers to pay back cash based on the flawed data.
Some victims were sent to prison or financially ruined, others were shunned by their communities while some took their own lives.
An inquiry into the Post Office and the Horizon IT scandal will continue next month.