Fujitsu staff feared mistakes being made as Post Office used ‘manipulated’ data
John Simpkins said he and his team worried about being ‘hauled over the coals’ if they made a mistake.
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Your support makes all the difference.Fujitsu staff feared being “hauled over the coals” after realising the Post Office was using “manipulated” audit data to criminally investigate subpostmasters, the Horizon IT inquiry heard.
John Simpkins, a team leader within Fujitsu’s software support centre (SSC), accepted that the team he worked in “downed tools” after learning the Post Office was using data that had “relevant” material missing in its investigations.
The inquiry heard Audit Record Query (ARQ) data – which recorded transactions made by subpostmasters – was “manipulated from its original source” and presented to the Post Office in a “filtered” format before they used it in criminal proceedings.
The SSC (software support centre) decided we're not happy doing this filtration if it's going to be used in court cases and we stopped
The inquiry heard the filtered format was missing “reference data” which contains information about what a Post Office counter can sell, how much it would sell it at and the steps taken during transactions.
Mr Simpkins previously answered questions at the inquiry in November 2022, where he said his colleague Anne Chambers was “very unhappy” after being asked to be an expert witness in a prosecution against a subpostmaster.
Ms Chambers, a retired Fujitsu engineer, gave evidence against East Yorkshire subpostmaster Lee Castleton, who was found to have a £25,000 shortfall at his branch.
He was made bankrupt after he lost his legal battle with the Post Office.
The inquiry previously heard Ms Chambers had told a colleague in August 2006, “I don’t really know what I’m doing”, as she investigated a subpostmaster’s branch accounts before a trial.
The inquiry was told that at some point after January 2011, Mr Simpkins and the rest of his team “downed tools” when they realised the Post Office was using filtered data rather than all the available audit data.
He told the inquiry: “The SSC decided we’re not happy doing this filtration if it’s going to be used in court cases and we stopped.”
Counsel to the inquiry Jason Beer KC then asked: “Why weren’t you happy?”
Mr Simpkins replied: “Because, again, leading on from Anne having to give evidence, we thought that if we were making the filter choices, they may want someone to come up and explain exactly why in a court case.”
Questioned on why he would not want to give evidence in court, Mr Simpkins said: “Because I would say it would be difficult to explain, technically, every single decision you’ve made out of 10,000 events why you decide to filter that.”
Mr Simpkins explained that he and other team leaders pushed their manager to agree with ceasing the filtering process.
Mr Beer continued: “Does it follow that before the SSC downed tools on this aspect of its work, none of you had been asked to explain in any formal way to either the security team or to the Post Office what you were doing and what filtering had occurred?”
The witness replied: “I imagine you’re correct, yes.”
Mr Beer then asked: “Would you understand that if a court is presented with a set of data, it would want to know what has been done and each of the steps that have been taken to produce that set of data?”
Mr Simpkins said: “Totally.”
The counsel to the inquiry continued: “That was, is this right, what led the SSC to ‘down tools’ as I’ve described it?”
The Fujitsu employee replied: “Yes, I think that’s fair.”
Mr Beer added: “And was that just a reluctance to be dragged into or become involved in court proceedings? Or was it because of difficulties in explaining the nature of the exercise that you were undertaking?”
Mr Simpkins said: “I would say it’s a partial both, but I would say it made a lot more sense to give them the full events than to give them a filtered version.”
The inquiry’s KC then asked: “So just to try and sum up your evidence, was it ‘we don’t want any involvement in the SSC in court proceedings after what happened to Anne’, was it ‘we are unhappy about the exercise that we’re being asked to undertake and we wouldn’t want that explored in court’, or ‘we know that there’s more information that could be revealed to subpostmasters to show the health of the system’?”
Mr Simpkins responded: “I think it was partially the first, Anne, and also partially that it is a manual process and you can obviously make mistakes.”
Mr Beer said: “So does that mean you wouldn’t want your homework subjected to scrutiny in a court?”
The witness replied: “No, I’m happy to have my homework (scrutinised) in a court, and I could go through and explain the reason why for each of them, but would you be hauled over the coals if you had made a mistake?
“Or if an event that according to a KEL (known error log), not financially impacting, later on becomes financially effecting because there’s been a change.”
Mr Beer then asked: “And you and your colleagues must have been sufficiently concerned that that was a realistic possibility to include that in your reasoning for not wishing to do it?”
Mr Simpkins said: “Correct.”
Mr Beer also asked the Fujitsu employee how audit data was extracted before it was handed to the Post Office.
The counsel to the inquiry said: “Did you understand that audit data, ARQ data, was extracted by Fujitsu and presented to the Post Office, it was presented in a filtered format?”
Mr Simpkins responded: “Yes, I’ve seen some ARQ extracts that look like they are filtered, and then put in Excel.”
Mr Beer continued: “So the data has been manipulated from its original source into a filtered format? Was that something you were aware of at the time?”
The Fujitsu witness replied: “Not really, because if we requested data for audit, which I believe we did, we got it back in the basic raw form.”
The statutory inquiry, which began in 2021 and is chaired by retired judge Sir Wyn Williams, has previously looked at the human impact of the scandal, the Horizon system rollout and the operation of the system, and is now looking into the action taken against subpostmasters.
The inquiry was established to ensure there was a “public summary of the failings which occurred with the Horizon IT system at the Post Office” and subsequently led to the wrongful convictions of subpostmasters.