Dmitry Nikolaev - stock.adobe.co

Post Office appointing third-party reviewer of current Horizon system

According to government representative on the Post Office board, an independent reviewer of Horizon is being appointed

The Post Office is in the process of appointing a third party to review its controversial Horizon computer system amid continued unexplained losses in branches.

During the latest hearing in the Post Office Horizon scandal public inquiry, Lorna Gratton, the civil servant who sits as a non-executive director of the Post Office on behalf of the government, said that during a board meeting on Tuesday 5 November, there had been a discussion over the current reliability of the Horizon system.

In relation to the discrepancies that subpostmasters continue to experience when using the Horizon system, she told the inquiry: “The Post Office executive team are in the process of appointing an independent third-party review of Horizon and its robustness.”

Over the past two decades, hundreds of subpostmasters have been wrongly convicted of crimes based on evidence from the flawed system – and problems persist. While the organisation is currently in the process of replacing Horizon, the timeline for doing so is uncertain.

Gratton said the Post Office is in contact with the Voice of the Postmaster group and the National Federation of Subpostmasters (NFSP) about the terms of reference of the review – which it will publish – and how they can be involved in the process. “It’s not going to be a sort of ‘sign off the terms of reference’ and get the product at the end, it’s going to be involvement throughout, with a view to publishing it and making it available to anyone that wants to see it,” she said.

She said the Post Office is also planning to invite subpostmasters into its operations centre in Chesterfield so it can be transparent on how it deals with discrepancies.

This comes on the back of a survey carried out by the public inquiry, which revealed that subpostmasters are still suffering unexplained shortfalls. The survey, carried out by YouGov, revealed that 57% of current subpostmasters have experienced unexplained shortfalls, including 19% reporting unexplained transactions and 14% having had transactions go missing.

Two-thirds of the subpostmasters surveyed (59%) said they were experiencing such issues at least once a month, and 69% said they have experienced an unexplained discrepancy on the Horizon system since January 2020.

Worryingly, three-quarters of surveyed subpostmasters said they have used their own branch money to cover discrepancies or resolved the issue themselves. The survey also found that nearly half (48%) were dissatisfied with how the discrepancies were resolved, compared with 19% who were satisfied.

The Post Office Horizon IT Inquiry is now in its seventh and final phase, which is focusing on the Post Office’s current practice and procedure, as well as recommendations for the future.


Computer Weekly first exposed the scandal in 2009, revealing the stories of seven subpostmasters and the problems they suffered due to Horizon accounting software, which led to the most widespread miscarriage of justice in British history (see below timeline of Computer Weekly articles about the scandal since 2009).

Timeline: Computer Weekly articles about the scandal since 2009

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