By bizn_fun 
Between 1999 and 2015, more than 900 sub-postmasters were wrongly prosecuted after the faulty Horizon IT system made it look like money was missing from branch accounts.
Some sub-postmasters went to prison, while many more were financially ruined and lost their livelihoods. Others died.
It has been described as the biggest miscarriage of justice in British legal history and has led to a long-running public inquiry into the scandal.
Countless evidence and testimonies have been heard, examined and reported during the inquiry, but a document which emerged in material published this month contained new, previously unknown, information.
The document shows that unbeknown to sub-postmasters, the two parties had a financial framework in place to manage discrepancies and for Fujitsu to fix problems or pay for them.
The Post Office denied throughout the criminal trials of sub-postmasters that errors or bugs could cause transaction shortfalls in branch accounts. It also denied in court that branch accounts could be remotely altered without the knowledge of sub-postmasters.
The document, external indicates the formal commercial arrangement was drawn up to deal with potential mismatches or “discrepancies” and where Fujitsu’s system was responsible, it was expected to correct false transactions or pay “liquidation damages”.
The disclosure also undermines the Post Office’s claim to the media and before Parliament in 2015 that it was not possible for Fujitsu to alter sub-postmasters’s transactions without their knowledge.
“The Post Office conducted both the criminal trials of postmasters and the group litigation of 2019 on the basis that it knew of no substantial problems with the Horizon system,” said Paul Marshall, senior barrister for sub-postmasters.
“Yet this shows that in 2006 there was a very big, recognised problem with Horizon maintaining data integrity between Post Office branch offices and Fujitsu,” he added.
“The Post Office, for 20 years, was saying the only explanation for shortfalls in branch accounts was postmaster incompetence or dishonesty.
“But the maintenance of data integrity was fundamental to the Post Office-Fujitsu contract – Fujitsu were unable to provide or assure this.”
The document implicitly acknowledges that data held on Horizon’s servers at Fujitsu’s headquarters could fail to match the transactions sub-postmasters had carried out at their branches.
It also adds to evidence that the Post Office was aware that the branch accounts of sub-postmasters could be remotely accessed. In the landmark Alan Bates vs Post Office case, for example, the organisation insisted that the software could not be accessed remotely by any other party.
Under the arrangements set out in the document, Fujitsu agreed to carry out a “reconciliation service” with the Post Office’s approval, where it was required to correct errors caused by bugs or defects or pay up to £150 per transaction in penalties known as “liquidated damages”.