For those who came in late, between 2000 and 2015 736 British sub-post office workers were arrested and jailed for fraud over accounting errors found by Fujitsu's Horizon Post Office’s computer system. However, it was later discovered that the computer code was buggy. To make matters worse, Fujitsu and the Post Office knew about the flaws but failed to reveal them during trials of subpostmasters.
According to the latest inquiry timetable, Fujitsu workers Anne Chambers and Gareth Jenkins, who are currently being investigated for perjury, will appear in front of inquiry chair Wyn Williams in the first week of May.
In December 2019, before handing down a judgment in the High Court, judge Peter Fraser said he was referring information to the DPP because he had concerns over the accuracy of evidence given in court by Fujitsu in previous trials of subpostmasters.
“Based on the knowledge that I have gained from conducting the trial and writing the Horizon issues judgment, I have very grave concerns regarding the veracity of evidence given by Fujitsu employees to other courts in previous proceedings about the known existence of bugs, errors and defects in the Horizon system,” Fraser said at the time.
A total of 736 subpostmasters and branch staff were prosecuted based on evidence from the Post Office’s Horizon accounting system used in branches between 2000 and 2015, many of whom were given prison sentences.
In January 2020, the director of public prosecutions referred concerns passed to him by judge Fraser to the Metropolitan Police. By November 2020, the Met had opened a criminal investigation into the two former Fujitsu workers.
Police working on the case have interviewed the former Fujitsu staff several times in the two years since the investigation was launched. It has interviewed at least one former subpostmaster who was a victim of the scandal.
The statutory public inquiry looking into the operation of the Horizon system, including training, assistance, resolution of disputes, knowledge and rectification of errors in the system.
Both former Fujitsu workers gave evidence during the earlier procurement, design, pilot, roll-out and modification phase of the inquiry.
In November last year, during a hearing in phase two of the inquiry, John Simpkin, Horizon system software support centre team leader at Fujitsu, who worked with Anne Chambers, said she had been “very unhappy” about being “maneuvered” into giving evidence.
Chambers appeared as an expert witness at the High Court during the case of Lee Castleton, a postmaster from Bridlington, East Yorkshire. Castleton was declared bankrupt after he refused to pay the Post Office £27,000 – money it said he owed because the accounts at his branch showed unexplained deficits over a 12-week period in 2004.
Simpkins told the inquiry: “After giving evidence, I know she was not very happy and never wanted to do it again. She fed back to our manager that she did not find it at all nice and I believe the manager pushed back that so it wouldn’t happen again.”
Gareth Jenkins was chief architect at Fujitsu, and was used as an expert witness in trials of subpostmasters accused of theft and false accounting. In 2013, a lawyer contracted by the Post Office, Simon Clarke of Cartwright King, told the Post Office that Jenkins should not be used as a witness as it was in breach of his duties.