A Post Office sign is displayed outside a branch in London, England. (Photo by Carl Court/Getty Images)

MORE than 500 postmasters were wrongly accused of stealing millions because of a glitch in the computer system used by the Post Office, the High Court heard yesterday (11) as a trial began to examine the reliability of the technology.

The Post Office is being sued by 550 current and former sub-postmasters who say the Horizon IT system used in their branches caused discrepancies, for which they were held accountable. A judge was told that postal chiefs tried to hide reports that the software had glitches.

Some claimants were accused of false accounting and they received jail sentences.
Seema Misra, 43, was jailed for theft when she was pregnant with her second son. She was running her village post office in West Byfleet, Surrey, when £74,609 went ‘missing’ from the branch’s accounts.

Patrick Green QC, appearing for the sub-postmasters, said experts had identified as many as 29 computer bugs in the Horizon system with “strong evidence of the bug causing a lasting discrepancy in branch accounts”.

He said a Post Office document in January 2017 had classified the Horizon computer system as “high risk.”

Anthony de Garr Robinson QC, appearing for the Post Office, said Horizon was “reliable” and said sub-postmasters had failed to provide any example of bugs causing false shortfalls, “let alone bugs causing the shortfalls of £18.7million that they claim not to be responsible for.”

He added: “[Their] suspicion of Horizon is driven by the natural human scepticism to technology.

“It is easy to blame the computer when something has gone wrong in a branch.”

The trial continues.