Ex-Fujitsu engineer tells Post Office inquiry Horizon was ‘working well’

A former IT engineer working with the Post Office has claimed that the Horizon accounting system was “in general … working well”, despite the software’s central role in a scandal described as the biggest miscarriage of justice in British history.

Gareth Jenkins, a former senior engineer at the contractor Fujitsu, on Tuesday faced the first of four days of questioning in an inquiry into the scandal.

The state-owned postal service wrongfully prosecuted 900 post office operators on the basis of alleged financial shortfalls in the accounts of their branches. However, many of those shortfalls were caused by bugs and errors in the accounting system that operators were forced to use.

Fujitsu designed and built the Horizon system at the centre of the scandal. The twice-postponed questioning of Jenkins, who was honoured as a “distinguished engineer” by the Japanese-owned company, will run for longer than any other witness during the inquiry.

Jenkins is part of a Metropolitan police investigation into possible perjury and perverting the course of justice. Before his testimony, Jenkins was reminded of his privilege against self-incrimination by the Horizon inquiry head, Wyn Williams.

The inquiry is in part examining whether the Post Office and contractors knew about the existence of bugs before deciding to go ahead with prosecutions, and whether they covered up vital evidence about Horizon during prosecutions.

A former Post Office financial investigator last week said Jenkins may have decided to remove references to “system failures” in Horizon in written testimony as an expert witness during one prosecution.

Jenkins told the inquiry that he believed the Horizon system was working well “most of the time”, and he did not agree with a 2019 high court judgment that found Horizon was not robust.

He was questioned repeatedly about the court’s findings by Jason Beer, a barrister for the inquiry. Asked whether he agreed that the software was “susceptible to accounting flaws”, Jenkins said: “There were some discrete bugs that caused problems to the accounts, but they were very discrete, and I believe they were all well controlled and managed at the time.”

Asked if bugs could cause shortfalls, he responded: “They could cause discrepancies in branch accounts but not at the sort of levels that have been talked about, and in general the systems were operating as they should.”

Questioned if he thought the Horizon program was working well, he said: “There were clearly problems during the pilots […] and there were clearly individual problems that affected individual branches. But in general I felt that the system was working well.”