Data from the scandal-hit Horizon system are still used in court proceedings, a Fujitsu employee told a public inquiry.
Rajbinder Sangha was asked on Tuesday whether the controversial system still provides data used for prosecutions.
“Yes, I think it is,” said Ms Sangha, who is a former member of Horizon maker Fujitsu’s fraud and litigation support office.
She was testifying to Sir Wyn Williams’ public inquiry into the Post Office scandal, which saw 736 sub-postmasters falsely convicted of crimes including theft and false accounting.
The Post Office uses Horizon, a computer system, to manage its 12,500 branch offices around the country, including keeping accounting records.
Yet in the 2000s and early 2010s, the system was generating false shortfalls in those records.
Post Office and Fujitsu bosses are now facing accusations that they knew about the software’s problems but deliberately covered them up.
The Post Office stopped prosecuting its own staff in 2015 but the Crown Prosecution Service (CPS) told The Telegraph that it continued with some postal prosecutions until as late as 2021.
Tuesday’s public inquiry hearing was shown internal messages sent by Gerald Barnes, a Fujitsu software developer, in 2008.
They recorded his concerns over “duplicate transactions” not being removed from Post Office electronic point of sale machines, and the potential for these to affect “a number of high-profile court cases in the pipeline”.
Two years later, Mr Barnes sent another message saying: “Our spreadsheets presented in court are liable to be brought into doubt if duplicate transactions are spotted.”
‘We thoroughly assess all material’
Hundreds of criminal cases were filed against sub-postmasters based on faulty Horizon data.
While the majority of these were brought privately by the Post Office, the CPS may have been involved in up to 99 of them.
A spokesman for the CPS said: “We carefully and thoroughly assess all material referred to us as part of an investigation before making a charging decision.
“Any evidence which might undermine the prosecution’s case or assists the defence will always be disclosed to the defence as part of our obligation to ensure a fair trial.”
The CPS has written to people it prosecuted based on Horizon data so that they can appeal against their convictions.