Data from the scandal-hit Horizon system is still used in court proceedings, a Fujitsu employee has said.
Rajbinder Sangha gave evidence at the Post Office Horizon IT inquiry on Tuesday where she raised concerns about a draft witness statement template handed to her shortly after joining in 2010, which said the software was operating properly “at all material times”.
She told the probe the template, which was potentially used to assist Post Office prosecutions, was concerning because “obviously bugs were in the system”.
Sam Stein KC, who represents a number of subpostmasters, asked Ms Sangha: “To your knowledge, is the Horizon system still being used to provide data that is used in court proceedings?”
The witness replied: “Yes, I think it is.”
Ms Sangha was taken through a number of emails and fault logs that detailed numerous problems with an updated version of the Horizon software called Horizon Online.
One Fujitsu software developer, Gerald Barnes, recorded his concerns over “duplicate transactions” not being removed from Post Office electronic point of sale service (EPOSS) machines, and the potential for it to impact “a number of high-profile court cases in the pipeline”.
In 2008, Mr Barnes described the lack of resilience to errors of the EPOSS machines, which were run by the Horizon system, as “endemic”.
Logging his concerns over duplicate transactions in November 2010, Mr Barnes said: “We are unaware of the presence of duplicate transactions.
“In the event that duplicates are retrieved and returned to (the Post Office) without our knowledge, the integrity of the data provided comes into question.
“The customer, and indeed the defence and the court, would assume that the duplicates were bona fide transactions and this would be incorrect.
“There are a number of high-profile court cases in the pipeline and it is imperative that we provide sound, accurate records.”
The inquiry heard that Mr Barnes said if the problem was not fixed, “our spreadsheets presented in court are liable to be brought into doubt if duplicate transactions are spotted”.
The issue was flagged as a “very significant problem” by security analyst Penny Thomas, prompting a response from Fujitsu executive Graham Welsh, which read: “In essence, we have a problem with the ARQ (Audit Request Queries) extraction tool.
“Under Horizon this would inhibit the duplicate transactions held from the audit server and thus supply evidence for court etc without duplicated records.
“However the (Horizon online) tool does not and thus duplicates records that cannot be differentiated are supplied as evidence.
“This could allow for legal challenges to the integrity of the system.”
Around a week before the issue was flagged, Ms Sangha, a former member of the fraud and litigation support office at Fujitsu, was sent the draft witness statement which read: “To the best of my knowledge and belief at all material times the system was operating properly, or if not, any respect in which it was not operating properly, or was out of operation was not such as to affect the information held within it.”
Counsel to the inquiry Julian Blake asked the witness: “Did it not cause you any concerns about the reliability of the statement?”
Ms Sangha, who is now a release management coordinator at the company, replied: “At the time, no, because I was not involved in producing a witness statement for going to court proceedings.”
Mr Blake continued: “Does it cause you any concern now?”
The witness replied: “Yes, it does.”
Asked why it caused her concerns now, Ms Sangha said: “Because obviously we had bugs in the system.”
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 probing the action taken against subpostmasters.
The inquiry was established to ensure there is 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.