900 more criminal prosecutions of subpostmasters could be unsafe because of IT failures

The Post Office has identified about 900 cases of subpostmasters who could have been wrongly prosecuted for crimes, including theft and false accounting, as a result of errors in the Horizon IT system that they use.

The scandal, which Computer Weekly made public in 2009 after an investigation, is today being described as one of the biggest miscarriages of justice in UK history (see timeline below).

The Horizon IT system from Fujitsu, which has been used by the Post Office since 1999, was for many years blamed by subpostmasters for account shortfalls. Computer Weekly has been investigating the story since late 2008, and during this time the Post Office has always denied that the computer system could be to blame for accounting shortfalls. It took a multimillion-pound group litigation order, 10 years later, to prove that it was.

Following its humiliating defeat in the High Court case, the Post Office promised to investigate historic cases. It has now announced that it is considering hundreds of cases of subpostmaster prosecutions that could be a result of Horizon faults. The Post Office said: “Following detailed record searches into the oldest cases from more than two decades ago, the review has currently identified around 900 cases prosecuted since the introduction of Horizon which may have relied on Horizon data, a rise in number from our previous statements when searches were continuing.”

It added: “The detail of the cases is being examined and the proportion involving Horizon evidence is still being determined.”

Subpostmasters had their lives wrecked and were humiliated by the actions of the Post Office. Some were sent to jail, forced to carry out community service, many were fined heavily, and they were forced to pay back money they had not taken. In fact, no money was missing – the alleged shortfalls were the result of errors in the computer system.

Computer Weekly made this public in 2009 after an investigation, and a High Court judgment in December 2019 proved the subpostmasters were right in blaming the computer system for errors and the Post Office was wrong in blaming them.

In the judgment in December, High Court judge Peter Fraser said the Post Office had exhibited “a simple institutional obstinacy or refusal to consider any possible alternatives to their view of Horizon, which was maintained regardless of the weight of factual evidence to the contrary”. 

He added: “That approach by the Post Office was continued, even though now there is also considerable expert evidence to the contrary as well, and much of it agreed expert evidence on the existence of numerous bugs.

“This approach by the Post Office has amounted, in reality, to bare assertions and denials that ignore what has actually occurred, at least so far as the witnesses called before me in the Horizon issues trial are concerned. It amounts to the 21st century equivalent of maintaining that the Earth is flat.”

The 550 subpostmasters who took the Post Office to court were awarded just under £58m in damages. Although this sounds a lot, after costs were taken out and the litigation funders paid, only about £11m remained. This amount does not even begin to repay financial losses, nevermind compensate subpostmaster victims for their suffering.

One former subpostmaster said: “My £8,500 in total doesn’t come anywhere near what I and my family went through. I went to jail and lost everything – job, house, everything I own.”

In March this year, the Criminal Cases Review Commission referred 39 appeals from subpostmasters against their criminal convictions to the Court of Appeal. This was the biggest group referral of potential miscarriages of justice in UK history and it looks likely hundreds more will join these appeals.

Helen Pitcher, chairman of the CCRC, told Computer Weekly that this was completely unprecedented, with the previous biggest group referral comprising 10 cases.  

She said there was likely to be more cases. “Of course we still have the other 22 cases under review, and more cases are coming to us with initial inquiries as a result of the announcement,” said Pitcher at the time.