Karl Flinders

IT expert who helped expose Post Office scandal offers to investigate second controversial system

IT expert Jason Coyne, who played a critical part in exposing the Post Office Horizon scandal, said he would examine the Capture System

The forensic IT expert who proved the Post Office’s Horizon software was error- and bug-ridden said he will carry out a similar examination of the organisation’s controversial Capture system if the government requests it.

Since the January ITV drama about the Post Office Horizon scandal, subpostmasters who experienced similar problems with a pre-Horizon system, known as Capture, have come forward.

Following news that the government will appoint an IT expert to look at the software system, Jason Coyne, who has a deep understanding of the Post Office Horizon case, offered his services.

He was used as an expert witness in the High Court group litigation order where a group of 555 subpostmasters sued the Post Office to prove the Horizon computer system used in branches contained errors that could cause unexplained accounting shortfalls that they were blamed for.

The trial was arguably the most important event in the unravelling of what is known today as the Post Office Horizon scandal, which saw lives ruined by the Post Office’s insistence that its subpostmasters were to blame for accounting shortfalls and not the computer system used to manage branch accounts. Most of the bugs, errors and defects now being discussed in the public inquiry are from Coyne’s 2019 reports.

But Coyne had encountered Horizon much earlier. In 2001, he was appointed to carry out an independent investigation as part of a legal battle between the Post Office and a subpostmaster. Then of Best Practice Group, he was a joint expert witness for both the Post Office and Julie Wolstenholme, subpostmaster at the Post Office branch in Cleveleys, Lancashire.

In 2001, the Post Office was suing Wolstenholme for the return of equipment used in the branch after her contract was terminated, but she said her employment was terminated unlawfully in a counterclaim that raised questions about the reliability of the Horizon computer system.

Defective hardware

Coyne’s 2003 report concluded the technology installed at Cleveleys was clearly defective in elements of its hardware, software or interfaces, and that “the majority of the errors in the fault logs could not be the making of Ms Wolstenholme”.

The Post Office tried to convince Coyne to change his views, which he refused to do.

The Post Office was given legal advice at the time that “in view of the negative expert’s report in this case regarding the computer system in place”, the Post Office’s claim against Wolstenholme would be likely to fail. The Post Office paid Wolstenholme an out-of-court settlement and, as part of it, forced her to sign a confidentiality agreement to not reveal the Horizon issues she was having.

In reaction to the government plan to appoint an IT expert to investigate Capture, Coyne said on X (formerly Twitter): “Using the same robust IT forensic investigation processes used in 2003 whilst looking at the Cleveleys Post Office and the 2017–2019 Horizon investigation commended by Judge Fraser, I would be happy to take on the Post Office Capture investigation, given appropriate instructions.”

Since the ITV drama, MP Kevan Jones, who has campaigned for victims of the Horizon scandal for over a decade, revealed cases of subpostmasters that had been affected by problems with the Capture system, in-house software written by the Post Office’s IT team.

Jones told Computer Weekly that he welcomed the government’s plan to appoint an IT expert to investigate the Capture system and would pass the suggestion on to government. “It is important that they appoint someone with the standing of Jason Coyne, to do this work.”

The Capture system, described as a “glorified spreadsheet”, was introduced in the mid-1990s, and was the first computerised system used to do accounts for many subpostmasters. Increasing numbers of them are coming forward in light of the Horizon scandal. Similarly to the Horizon software from Fujitsu, branch managers began experiencing unexplained shortfalls, which they were blamed for.

Steve Marston, a former subpostmaster in Bury, Lancashire, and Steve Lewis, a former subpostmaster in South Wales, are two prominent cases.

When Lewis suffered unexplained losses, he was told by the Post Office that he was an isolated case. He lost his business, had to sell his home and suffered mental health issues, with related relationship troubles. He recently told Computer Weekly it’s a positive sign that the government “appears” to be taking the Capture issues seriously.

Marston was prosecuted in 1996 for theft and false accounting following an unexplained shortfall of nearly £80,000. He said he had never had any problems using the paper-based accounting system. This changed when his branch, which he ran from 1973, began using the Capture system.

Marston said he felt pressured into using the system at a time when many branches were being closed by the Post Office. He’d had no problems for two decades using manual accounting processes, but within two years of using Capture, he ran up a debt of £79,000.

He covered the losses with his own money, but it kept getting worse. After an audit revealed a loss he couldn’t fully cover out of his own pocket, he was advised to plead guilty to theft and fraud to avoid jail. The judge took into account two bravery awards Marston had received for standing up to armed robbers, saving him a jail sentence. He was given a 12-month suspended sentence, lost his home and business, and went bankrupt.

Marston said he hopes to get justice. “We are pleased that ministers and others are taking notice,” he said. “We want to know if there is a route to have my conviction overturned.”

The Post Office scandal was first exposed by Computer Weekly in 2009, revealing the stories of seven subpostmasters and the problems they suffered due to accounting software (see timeline of Computer Weekly articles about the scandal below).


• Also read: What you need to know about the Horizon scandal

• Also watch: ITV’s documentary – Mr Bates vs The Post Office: The real story


Read all Computer Weekly articles about the scandal since 2009

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