One of the most frustrating elements of the Post Office’s Horizon computer scandal was the institutional inertia around it.

Many people, bodies, organisations, and organizations knew that there was something seriously wrong over the years. This was because they were informed. They remained silent for many years.

Julian Lewis, Conservative MP and the only person to have enough detail to call the episode in parliament one of worst public disasters since the infected Blood Scandal in 2014, said that it was just last year.

The government is partly responsible. It had pressed the Post Office to make more money by expanding its reach as a financial services provider — selling insurance, mortgages, issuing credit cards and installing cash machines.

The Post Office scandal left hundreds of innocent people criminalised while Paula Vennells was chief

The Post Office scandal saw hundreds of innocent victims criminalized while Paula Vennells, chief of the Post Office, was in charge.

Every link in the Horizon IT chain needed to be considered bulletproof in order for this project to succeed. There was no way to acknowledge any system flaws.

There were no alarms ringing and there were not any questions being asked. Nobody shook the boat.

This scandal was largely caused by a lack of interest and oversight from the government in the Post Office.

Nine ministers, pretending to be in charge of the Post Office over the last 11 years, have blithely repeated any assurances given.

The scandal was unravelling and the Government refused to help in any way. This may have been because it knew that its ministers had to know exactly what was happening.

The legal system hasn’t fared so well. The sheer number of Post Office-led prosecutions during this 15-year period — more than one a week — should have raised eyebrows. However, no one from the Justice System or Government was aware of the situation.

Another contributor to the scandal was the very organisation set up to protect the interests of Subpostmasters — its equivalent of a trade union. Unions can act as canaries at the bottom of a coal mine and bring issues to our attention. But not the National Federation of Subpostmasters (NFSP), known as ‘the Fed’.

When automation of the Horizon system was proposed, the NFSP welcomed it whole-heartedly as the deal of the century, and it sold the network to its members at national and regional conferences, promising a golden future

The NFSP embraced the proposal to automate the Horizon system wholeheartedly. At national and regional conferences it also sold the network, promising a great future.

‘It’s more like a Rotary Club than anything else,’ I was told. ‘They seem far more interested in holding annual dinners and congratulating each other than doing much else.’

Subpostmasters are technically self-employed, they run their own businesses and are entrepreneurial, self-reliant, small-‘c’ conservatives who instinctively trust officialdom and state institutions.

However, they expect their membership to protect their interests. They also want their relationship to the Post Office to be viewed as a partnership.

The NFSP is proud to display this self-image, which is one that the Post Office enjoys.

The NFSP embraced the proposal to automate the Horizon system wholeheartedly. They sold the network at its national and regional conferences to their members, promising a golden tomorrow. It was ‘a new dawn’.

With full support from the NFSP the Post Office placed a wager on Horizon. The Post Office could not afford to fail.

It was crucial to ensure the integrity, credibility and operation of the system. Since its initial rollout, the NFSP was unaffected by any criticism.

As the Post Office went on its prosecution spree, any journalist approaching the NFSP would be told (in language strikingly similar to the Post Office’s) that Horizon was ‘robust’. Off-the-record directions about Subpostmasters’ potentially dangerous convictions were not granted. They received dark hints suggesting that they might be making a story.

Its official line, trotted out to journalists such as me, was that ‘the NFSP has seen no evidence to suggest that Horizon has been at fault. We have full confidence in the accuracy of the system’.

Postmasters accused of theft by Post Office celebrate outside the High Court In London after they had their convictions overturned

Postmasters accused by theft of Post Office celebrated outside the High Court In London, after they were acquitted.

The NFSP’s decision to avoid voicing any public concerns about Horizon made it complicit in the misery and chaos endured over the next two decades by desperate Subpostmasters, under threat of prosecution or losing their livelihoods. They were publicly punished by the NFSP and allowed to drown.

When wronged Subpostmaster Alan Bates took his campaign to a regional conference and handed out leaflets, a rep walked past saying: ‘Don’t talk to him — he’s a thief.’ Mr Bates was forced to set up his own campaigning group. It was the sole source of criticism for the Post Office IT system in 2004.

When one member of the NFSP executive committee voiced his concerns about Horizon to his Fed colleagues, he recalls: ‘They all just laughed . . .

‘They just wouldn’t believe that balancing problems could be caused by technical issues. Because they believed what the Post Office told them.’

Any errors had to be the Subpostmaster’s fault.

Scandalously, though, there was a major chink in the Fed’s case. Evidence in a court case revealed that the NFSP had been entirely funded by. . . Post Office What’s more, it had accepted this funding arrangement in return for agreeing to a Post Office cost-saving transformation which would cut most Subpostmasters’ salaries to the bone.

In this signed (and secret) commitment, the Fed expressly agreed not to engage in ‘any public activity which may prevent Post Office Ltd from implementing any of its initiatives, policies or strategies’.

The judge’s comments were damning. He concluded: ‘The NFSP is not an organisation independent of the Post Office, in the sense that word is usually understood. The NFSP is effectively controlled by the Post Office. Evidence also supports the existence of the NFSP . . has put its own interests and the funding of its future above the interests of its members.’ In other words, the Subpostmasters had been catastrophically let down by those who were supposed to protect their interests.

It is not the Post Office staff that are to blame most for this scandal. With its ambitious, flawed IT project and resulting scandal, it created it in the first instance. It then cleaned its collective feet of it.

Martin Griffiths tragically took his own life after being wrongly accused in the Post Office Horizon scandal. He ran Hope Farm Road Subpost Office in Great Sutton, Cheshire for 13 years

Martin Griffiths took his life following being falsely accused in connection with the Post Office Horizon scandal. For 13 years, he ran Hope Farm Road Subpost Office located in Great Sutton (Cheshire).

Worse, even worse was the failure to give crucial information and support to MPs or campaigners when it became aware that it could have been negligent in unsafe prosecutions for its Subpostmasters.

As the truth emerged in court, judges were scathing about the organisation’s credibility.

In one High Court judgment, Mr Justice Fraser said he had heard evidence from two senior Post Office executives — Angela van den Bogerd and Nick Beal — and in future would accept what they said only if it was ‘clearly and incontrovertibly corroborated by contemporaneous documents’.

That, said a leading QC, ‘is the judicial equivalent of not trusting them to tell him if the sky is blue, without going outside to check’.

How did the Horizon computer system go wrong and what was it?

Between 1999 and 2015, hundreds of postmasters were sacked or prosecuted after money appeared to go missing from their branch accounts (file image)

It was reported that hundreds of postmasters lost money from branch accounts between 1999 and 2015. 

From 1999 onwards, the Post Office introduced Horizon, an innovative IT system that was developed by Fujitsu in Japan.

This system could be used to do transactions, stocktaking and accounting. Subpostmasters raised concerns about the system’s shortcomings after reporting shortfalls, some which were thousands of pounds.  

Subpostmasters tried to fill the gap using their own money and even remortgaging homes to try to fix an error.

The glitches led to hundreds of subpostmasters being fired or prosecuted between 1999 and 2015. Horizon’s flaws were blamed by the ex-workers, who claimed that there were problems with the IT system. However, the Post Office insisted that no problem existed.

Post Office forced postmasters to plead guilty in case after case to charges they didn’t commit.

Others who weren’t convicted were forced out of work or required to repay thousands of pounds in’missing money’.

The Post Office spent £32million to deny any fault in their IT system, before capitulating. 

The following are some of the highlights. Postmasters and postmistresses claimed that the scandal had ruined their lives, as they tried to deal with it. Some of them were pregnant, or even had children when they were convicted and imprisoned.

The courts heard from families that marriages fell apart, and how stress may have led to addiction, health problems, premature death, or even suicide.

But denial and evasion were in the Post Office’s DNA. When, in 2015, former Subpostmaster Parmod Kalia realised from Panorama reports he’d seen — 14 years too late for him — that he had been wrongly jailed, he wrote to Paula Vennells, who was the Post Office chief executive from 2012 to 2019. He told her that what had happened to him when the figures on his computer terminal didn’t add up must have been as a result of a Horizon error.

It is typical of Parmod’s decency that he did not demand that she re-open or review his case. Parmod simply asked for an explanation for the Post Office’s actions towards him.

Angela van den Bogerd was the one to reply.

She told him that the Post Office had ‘exhaustively investigated’ Horizon and had not identified ‘any transaction caused by a technical fault with Horizon which resulted in a postmaster wrongly being held responsible for a loss of money’.

She added that there was no evidence of transactions recorded by branches ‘being altered through “remote access” to the system. Horizon doesn’t have the functionality to allow Fujitsu or Post Office access. [the manufacturer of the system] to edit or delete the transactions recorded by branches.’

The Post Office admitted in court just over a year later that remote access was possible.

Since Horizon was launched, the Post Office took action when discrepancies were found. This is fair and necessary to protect fraudsters.

Horizon provided a view into each branch of the country to area managers, cash management teams and investigators. These people were always on the alert for missing money and false accounting. After suspicious activity was identified auditors were able to visit a Post Office branch and request access at the counter in order to assess what was going on.

Unfortunately, a lot of Post Office auditors weren’t very good at their jobs. According to expert evidence given to a Parliamentary Select Committee, ‘they simply assume the balances on Horizon are correct, compare them with those in the branch and prosecute the Subpostmasters if the balances in the branch are less than those on Horizon.

‘No vouching of transactions whatsoever is undertaken by Post Office auditors. Using the term “audit” to describe this intervention gives their actions a veneer of professionalism and depth of analysis which is entirely absent.’

Paula Vennells became the Post Office Chief Executive in 2012. She seemed like the right choice. She’d had a slew of big corporate jobs in the private sector and had joined the Post Office five years earlier. She felt it was high time to do something for others.

‘It’s about community, too,’ she said. ‘People care desperately for the Post Office. Very often it’s the Subpostmaster or mistress who notices that an elderly customer hasn’t turned up recently and finds out what’s happened to them.’

She may have felt a strong moral or spiritual motive to join the Post Office.

Non-stipendiary Church of England Minister, The Reverend Vennells once spoke at a conference about how she got Biblical inspiration from young King Solomon. She also shared how he wished to lead his people with justice.

Her brief from David Cameron’s government was for the Post Office to become operationally profitable by 2020, and she embraced the challenge. She was disappointed to discover that the Post Office was overflowing with plodders.

Former post office worker Wendy Buffrey (left), from Cheltenham, celebrates outside the Royal Courts of Justice, London, after having her conviction overturned by the Court of Appeal

Wendy Buffrey, a former post office worker, from Cheltenham celebrates in front of the Royal Courts of Justice London after her conviction was overturned by Court of Appeal

Many of them started their careers as clerks at the counter or in post offices and then worked their way to middle management. By keeping their heads down for 20 or 30 years, they were rewarded for their loyalty with jobs they didn’t really have the capacity for. Paula Vennells saw this and began to train staff to help improve performance.

But there were far too many old-timers whose identity was bound up in the Post Office’s own self-image. Because they saw the Post Office as virtue, then they themselves were also virtuous. They saw criticism of the Post Office as a direct attack against their personal integrity.

One of the new intake was shocked by what he found, likening prevailing attitudes to ‘a lifebuoy which became a cage . . . It leads to cultural blindness.’

Furthermore, ‘anything that could get in the way of that 2020 target was logged as a risk to be managed and minimised’.

Aged 19, Tracy Felstead, 38 from Telford, found that £11,500 had 'gone missing' from her south London post office when she returned from holiday.

Aged 19, Tracy Felstead, 38 from Telford, found that £11,500 had ‘gone missing’ from her south London post office when she returned from holiday.

Janet Skinner (left) and Tracy Felstead outside the Royal Courts of Justice, London, ahead of their appeal against a conviction of theft, fraud and false accounting

Janet Skinner (left), and Tracy Felstead, outside of the Royal Courts of Justice in London before they appeal against a conviction for theft, fraud, and false accounting

Former Post Office worker Janet Skinner (centre) hugs family members after having her conviction relating to the Horizon IT scandal overturned in April of this year

Janet Skinner, a former Post Office employee (center), hugs her family after she was convicted in relation to the Horizon IT scam.

Vennells was, according to me, unhappy about the situation. Although she believed that the systems were working well, she said she felt the need to solve the problem.

Second Sight, an independent team of forensic accountants was brought in to conduct a detailed review of the business and IT processes. But its leader, Ron Warmington, was soon bemoaning ‘the smokescreen’ they faced as their investigation progressed.

He detected a culture of bureaucratic intransigence: ‘We asked for short, easy-to-understand, honest and complete answers [to our questions] and what we get are highly technical, multi-page responses that appear to have been crafted so as to avoid actually giving any answers.’

And when it looked as though, far from confirming that everything was hunky dory, Second Sight was proposing to criticise the Post Office’s training, support, investigation and basic treatment of Subpostmasters, they came under direct pressure to water down their criticisms and language.

Vijay Parekh (centre) with wife Gita (left) and daughter Bhavisha after his conviction was overturned in April, joining dozens of others, who were all blamed for disappearing funds at their respective Post Office branches, which was later found to be due to a faulty computer system

Vijay Parekh, left, with Gita, his wife, and their daughter Bhavisha, after his April conviction was overturned. He was one of many people who had been accused for stealing funds from the Post Office branches in which they worked. This was later discovered to have been due to an error in the computer system.

The report was particularly critical of the way the emphasis of the Post Office investigators was on ‘asset recovery solutions’ — ie, getting its money back — rather than identifying and fixing the underlying problems which were causing the losses to appear in Subpostmasters’ accounts.

But the Post Office stuck to its old mantra — Horizon contained no systemic errors. Don’t blame the IT.

A growing number of MPs were alerted to the Post Office by constituents. They called for a meeting with senior management.

The Select Committee of MPs questioned the Post Office Top Team and exposed yet more evidence of corporate dysfunctionality.

It evolved a rhythmic pattern. Paula Vennells answered a question that the MPs asked with an irrelevant answer.

They would press her to give the answer to the actual question, and it would turn out she either didn’t know or decided she needed to take some offline advice before answering. Angela van den Bogerd would take the question and answer it.

After one such encounter about the non-disclosure of legal files by the Post Office, one frustrated MP was left telling her: ‘I asked you a question and you haven’t given me a straight answer, so I will draw my own conclusions.’ Towards the end of the session, Ian Henderson of Second Sight put on public record his concerns about the Post Office’s woeful investigation function. He was ‘very concerned’ about many of the prosecution cases brought by the Post Office against Subpostmasters.

Here was an independent investigator — brought in by the Post Office itself, remember — giving evidence to a parliamentary inquiry that a publicly owned company had brought criminal prosecutions without sufficient evidence, and that miscarriages of justice had very possibly occurred.

Paula Vennells denied that. ‘We have no evidence of that,’ she said.

Former subpostmasters Janet Skinner, Seema Misra and Tracy Felstead outside the Royal Courts of Justice in March this year

Former subpostmasters Janet Skinner, Seema Misra and Tracy Felstead outside the Royal Courts of Justice in March this year

However, pressure was growing on her. In an interview for Panorama, former Tory MP James Arbuthnot called on her to resign and said that the Post Office’s behaviour had been ‘disgusting’, an ‘abuse of power’ and ‘one of the most shocking things that I came across while I was a member of parliament’. The brother of a convicted Subpostmaster who had just died wrote to Ms Vennells telling her of his death and said that it had been due ‘in no small part to the seven years of stress he suffered as one of the Subpostmasters who have all been wronged terribly as a result of the Post Office negligence’.

Ms Vennells did not respond, leaving her ‘correspondence manager’ to send condolences on her behalf. In 2018, Ms. Vennells was given a CBE in recognition of her service to the Post Office.

Within weeks, Vennells had slipped further into the establishment’s warm embrace, announcing she would be leaving the Post Office to take up a board position at the Cabinet Office and chairmanship of Imperial College Healthcare NHS Trust. As questions about Vennells’ time at the Post Office piled up, neither job was sustainable.

But the Reverend Vennells continued to preach on moral matters throughout the Church of England’s Bromham Benefice in Bedfordshire. She was ‘deeply saddened’ by the Subpostmasters’ accounts of their suffering that were reported during the Court of Appeal proceedings.

The Communication Workers Union called for her to be stripped of her CBE and demanded a criminal investigation into those at the Post Office ‘who put these loyal postmasters in this situation’.

After seven years of asking, I wanted to know if Paula Vennells was now ready for me to have an interview. So I visited her through her legal team.

Her house was in Bedfordshire, and it is a rambling cottage with manicured gardens. I drove there. The house is what Subpostmasters must clean in order make ends meet.

The place was expected to be empty. But, I found a room lit up. It was a kitchen and Ms Vennells was standing in it. We made eye contact. It was a joy to be home. So, I went up to the front door to knock, telling her who I was and why.

There was no reply. I knocked louder. I turned around and went back to the kitchen windows. I saw that the lights were off, and there was no one in the room. Semi-dark steams two unopened plates of vegetable and pork chops.

Was Vennells hiding now? Hiding?

With my polite requests for an interview, I returned to the front door. Silence.

After trying one more time, I gave up. My latest attempt to hold anyone accountable had been a failure.

Horizon was, short-hand, a poorly designed and badly implemented IT disaster. It was operated in an environment where a flawed system and incompetent people were able to destroy others’ lives.

Well, as far as anyone being punished or censured in writing for contributing to, perpetuating, or trying cover up the Great Post Office Scandal. . . I won’t hold my breath.

Adapted from The Great Post Office Scandal, by Nick Wallis (£25, Bath Publishing) © Nick Wallis 2021. To order for £22.50 (offer valid till 28/11/21; UK P&P free), go to or call 020 3176 2937.