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The Post Office Horizon scandal inquiry findings could put pressure on the government to change the controversial rule on the use of computer evidence in court which contributed to wrongful convictions and punishment, destroying the lives of hundreds of subpostmasters.
Last week, the controversial part of the Police and Criminal Evidence (PACE) Act was brought into the statutory public inquiry, signalling that it could form an important part of the current phase of the hearings.
One of the goals set for the inquiry, which is examining why subpostmasters’ lives were destroyed based on evidence from the Post Office’s error-prone computer system, is to ensure nothing like this can ever happen again. The law on computer evidence therefore must be scrutinised and judged upon or something similar will happen again, say legal and IT experts.
Hundreds of subpostmasters were prosecuted based on evidence from software used in Post Office branches, which under current rules is presumed in court to have been working properly unless proven otherwise. Using its private prosecution and investigation powers over 15 years, the Post Office prosecuted 736 subpostmasters, suspected of stealing from branches, based on evidence from the Horizon retail and accounting system from Fujitsu.
In 2009, a Computer Weekly investigation first revealed that subpostmasters were being blamed for unexplained accounting shortfalls, which they believed to be caused by software errors (see all of Computer Weekly’s articles on the scandal below).
As the Post Office scandal was unwrapped, it emerged that the evidence from the Post Office’s Horizon computer system, used in thousands of branches, was error prone, with figures that should not have been relied on in court.
A High Court group litigation order (GLO) in 2018/19 saw a group of subpostmasters, led by the unmovable former subpostmaster Alan Bates, prove that computer errors caused unexplained accounting shortfalls. A total of 86 former subpostmasters have so far had criminal convictions overturned, and more are expected. Many of these subpostmasters were sent to prison, and those prosecuted suffered huge financial difficulties and stress, with many suffering bankruptcy.
Computer evidence rules
It is today seen as one of the biggest miscarriages of justice in British history, one that was made possible because of a change to the rules around computer evidence brought in at the same time the Horizon system was rolled out to thousands of Post Office branches.
There is a significant body of opinion, in IT and legal circles, that agrees that change to the guidance on the use of computer evidence in court must be made to avoid miscarriages of justice, like those experienced by subpostmasters. A better understanding of the role of rules on computer evidence could stir a public becoming increasingly aware of what happened.
In 1999, a presumption was introduced into law on how courts should consider electronic evidence. The rule followed a Law Commission recommendation for courts to presume that a computer system has operated correctly unless there is explicit evidence to the contrary. This legal presumption replaced a section of the PACE Act 1984, which stated that computer evidence should be subject to proof that it was in fact operating properly.
The new rule made it easier for the Post Office, through its private prosecution powers, to convict subpostmasters for financial crimes when there were accounting shortfalls based on data from the Horizon system.
As Computer Weekly revealed in 2021, following a response to a freedom of information (FoI) request made by computer scientist Steven Murdoch at University College London, the Post Office wrote to the Law Commission in 1995 when the law change was being proposed, and said the rule at the time, which said computer evidence should be subject to proof that it was in fact operating properly at the time, was “somewhat onerous” when prosecuting people charged with crimes, such as the subpostmasters that run and own its branches.
Response to Law Commission request
In response to a Law Commission request for feedback on proposals to change the rules, the Post Office wrote: “I consider that computer evidence is, in principal, no different from any other sort of evidence, and it should, in general terms, be admissible, so that any argument in court would be related to its weight rather than its admissibility. I therefore consider that there should be a presumption that the machine is in working order, etc, and if the defence wish to argue otherwise, then clearly, they should be able to do so. At present, I therefore consider the evidential requirements to be far too strict and can hamper prosecutions.”
It continued: “In the event of a subpostmaster being prosecuted for theft or false accounting, the Post Office may need to rely upon the computerised accounting records. The subpostmaster is frequently the only person who can give the evidence required by Section 69 of [PACE]. In the absence of admissions or other direct evidence the Post Office may not be able to prove the case solely on the ground of being unable to satisfy the technical requirements of Section 69 of [PACE].”
The Post Office was making clear that prosecutions would be difficult unless the computer evidence is presumed to be accurate. What is common knowledge today is that the Horizon software, which Post Office branches used, produced figures that were not accurate at all times. This data was used to successfully prosecute hundreds of people.
During a hearing at the public inquiry last week, this letter from the Post Office was highlighted by barristers, signalling that this will play a part in the current stage of the inquiry.
There have been loud calls for something to be done about this law, seen by one lawyer as “wrong-headed”. Lawyers, tech experts and politicians have called on government to replace it.
Last year, Kevan Jones, Labour MP and long-time campaigner for justice for the subpostmasters affected by the Horizon scandal, asked the secretary of state for justice whether the government planned to assess the legal presumption of reliability of computer evidence.
In response, Conservative MP and then parliamentary under-secretary of state for justice, James Cartlidge, said: “We have no plans to review the presumption, as it has wide application and is rebuttable if there is evidence to the contrary.” He said the current public inquiry into the Post Office Horizon scandal would advise the government on the matter.
At the time, Stephen Mason, a non-practicing barrister and editor of the practitioner text for judges and lawyers, Electronic Evidence, who has been trying to persuade the legal profession for over a decade to take the subject seriously, said the government could be waiting to reconsider the matter “should Horizon Inquiry chair Wyn Williams make any recommendations on this specific issue when he submits his report”.
Mason told Computer Weekly it is essential that the guidance on computer evidence changes if the inquiry is to reduce the risk of further miscarriages of justice: “Courts should be told to consider computer evidence in the context of the known errors in the software that produced it and the strength of evidence that the software was developed to high professional standards - evidence should be provided - and maintained and regularly audited to high professional standards.”
He added: “If the software was not developed to relevant professional standards, the known error logs will be incomplete, and the software and the evidence from it presumed unreliable and of no probative value.”
Ministry of Justice
When the government said last year it had no plans to review the presumption, Mason said that if the government does not intend to do anything, then the least the Ministry of Justice can do is implement the recommendations made by barrister Paul Marshall and others.
Marshall, who represented subpostmasters who successfully overturned wrongful convictions by the Post Office, was invited in August 2020 by MP Alex Chalk at the Ministry of Justice to submit a paper to the department on suggestions for improving the existing approach to the proof in court proceedings of computer-derived evidence. The paper was submitted to the MoJ and published.
It recommended that when electronic evidence is used in legal proceedings, the party relying on the electronic evidence should automatically provide sufficient details of their systems to demonstrate that they are professionally managed.
Marshall told Computer Weekly that “it is difficult to imagine a more wrong-headed set of propositions” than the change to the rule on computer evidence that was introduced in 1999. He said the judgements of High Court judge Peter Fraser in the 2019 group litigation action, where subpostmasters proved that computer errors were to blame for unexplained losses, exposed “the fundamental flaws in the Law Commission’s analysis and in its conclusions. It also exposes, tragically, how strikingly unfairly the presumption that a computer is working properly may operate in legal proceedings.”
He said that since the change to the rules, it has been assumed as a matter of law “that the computer worked properly unless it can be shown that that assumption cannot safely apply”, and that this puts an evidential burden on someone, responding to computer evidence, that in many cases they are simply incapable of doing, “for the simple reason they do not – and cannot know”.
“The Horizon scandal in large part is the consequence of the Law Commission’s misconceived recommendations to parliament that PACE 1984 should be repealed,” said Marshall.
“The timeline of Post Office prosecutions matches exactly the period from which it was repealed. The Post Office had supported repeal – presumably to make its prosecutions for alleged ‘shortfalls’ easier and reversing the burden of proof was of immense practical value to the Post Office.
“The idea that problems with computers are usually apparent, as suggested by the Law Commission, is simply fatuous nonsense. The Boeing 737 Max disasters in 2018 and 2019 were due to software errors, which had lay dormant in the flight control software, probably for years. All computer programs contain bugs. Even safety critical software, such as in aircraft or medical equipment, has multiple bugs in it. These are facts that are insufficiently understood, as the Horizon prosecutions and false convictions all-too-painfully reveal.”
Richard Moorhead, professor of law and professional ethics at the University of Exeter, said: “Post Office cases show both it and the courts take an insufficiently forensic attitude to computer evidence and that while changing the law might well help, this is also about the courts being thoughtful about expert evidence and disclosure generally.”
The odds were stacked against the subpostmasters. Proving that the Horizon system was in error at the time of an unexplained loss would be almost impossible for most subpostmasters.
Speaking to Computer Weekly in 2021, after the government said it had no plans to review the presumption, Stephen Castell, computer software and systems expert witness and chairman of Castell Consulting, said the presumption “is and always was just plain wrong”.
He challenged Cartlidge’s claim on behalf of the government that the presumption has wide application and is rebuttable: “While the presumption may in principle be rebuttable, that rarely happens effectively in practice, since the defendant has meagre resources compared with the state, the prosecution.”
When subpostmasters accused of theft or false accounting challenged the Post Office, it told them they were the only one having problems. If they persisted in challenging, the Post Office failed to give suspects access to evidence or outspent them in court, to win cases. When subpostmasters did receive expert help, it was often a different case, with the Post Office backing off and not prosecuting, through fear of the truth coming out.
Andy Clark, visiting professor in information security at Royal Holloway University of London and director at information security and expert witness company Primary Key Associates, told Computer Weekly in 2015 that 10 years earlier, he was called as a witness for the defence in a case brought by the Post Office against a subpostmaster. After seeing the Post Office Horizon accounting system in action, he said it was quickly apparent there were questions to ask about its integrity. After asking the Post Office these questions, the Post Office dropped the case, he said.
The Post Office knew that if evidence of Horizon errors got into the hands of subpostmasters it was prosecuting they would suddenly find it much harder to prosecute. A recent Horizon inquiry hearing revealed that the Post Office had a policy of not sharing evidence of computer errors with subpostmasters.
A Post Office internal document for its staff investigating subpostmasters suspected of stealing warned that the inclusion of information on “significant failures” in reports that the suspected subpostmasters were sent, could reduce the chances of a successful prosecution of a suspect and/or cause “significant damage” to the Post Office’s business. It said this information about “significant” failures, including in regard to product integrity, must be “confined solely” to a report which was sent to its own lawyers.
From the roll-out of the Horizon system in 1999/2000 right up until the High Court GLO in 2018/19, the Post Office claimed there were no Horizon errors that could cause unexplained shortfalls. If subpostmasters had problems and suspected the computer was to blame, they were told they were the only one having problems.
During the public inquiry, former Post Office senior staff have claimed they were not aware of any errors with Horizon. One witness recently admitted being guilty of “absorbing the group think within the Post Office that [Horizon] was a good robust system”.
James Christie, an IT expert with extensive experience of software development, IT audit, testing and security management in the IT outsourcing industry, said it appeared the government was buying time and passing the buck to the Post Office Inquiry, when it announced it would not review the rule on computer evidence.
He said the case for reforming the presumption is overwhelming, and “the government should have the resolve to initiate reform without waiting to see what Wyn Williams says.”
“If this presumption is not reformed, the Post Office scandal will not be the last,” said Christie. “It is long past time to act, and it is very disappointing to see the government playing for time.”
Murdoch at University College London said he would like to see the inquiry examine the effect of the presumption that computer evidence is reliable, in contributing to the miscarriages of justice and other problems related to Horizon: “While inadequate disclosure has been and continues to be a problem, the presumption has allowed the Post Office to prosecute subpostmasters without being required to support this with evidence as to the reliability of Horizon.”
The coming weeks are an opportunity for the controversial law to come into the gaze of the public.
- May 2009: Bankruptcy, prosecution and disrupted livelihoods – postmasters tell their story.
- September 2009: Postmasters form action group after accounts shortfall.
- November 2009: Post Office theft case deferred over IT questions.
- May 2010: A pilot of the new Horizon Online system at Royal Mail has been scaled back after connectivity problems and outages.
- February 2011: Post Office faces legal action over alleged accounting system failures.
- October 2011: 85 subpostmasters seek legal support in claims against Post Office computer system.
- June 2012: Post Office launches external review of system at centre of legal disputes.
- January 2013: Post Office admits Horizon system needs more investigation.
- January 2013: Post Office announces amnesty for Horizon evidence.
- January 2013: Post Office wants to get to bottom of IT system allegations.
- June 2013: Investigation into Post Office accounting system to drill down on strongest cases.
- July 2013: Post Office Horizon system investigation reveals concerns.
- October 2013: End in sight for subpostmaster claims against Post Office’s Horizon accounting system.
- October 2013: Former Lord Justice of Appeal Hooper joins Post Office Horizon investigation.
- November 2013: 150 subpostmasters file claims over “faulty” Horizon accounting system.
- September 2014: Fresh questions raised over Post Office IT system’s role in fraud cases.
- December 2014: MPs blast Post Office over IT system investigation and remove backing.
- December 2014: Why MPs lost faith in the Post Office’s IT investigation, but vowed to fight on.
- December 2014: MPs to debate subpostmaster IT injustice claims.
- December 2014: MP accuses Post Office of acting ‘duplicitously’ in IT investigation.
- January 2015: MPs force inquiry into Post Office subpostmaster mediation scheme.
- January 2015: Post Office faces grilling by MPs over Horizon accounting system.
- February 2015: Post Office CIO will talk to any subpostmaster about IT problems, promises CEO.
- March 2015: Post Office ends working group for IT system investigation day before potentially damaging report.
- March 2015: MPs seek reassurance over Post Office mediation scheme.
- March 2015: Retiring MP aims to uncover truth of alleged Post Office computer system problems.
- April 2015: Post Office failed to investigate account shortfalls before legal action, report claims.
- April 2015: Criminal Courts Review Commission set to review subpostmasters’ claims of wrongful prosecution.
- June 2015: Post Office looking to replace controversial Horizon system with IBM, says MP.
- July 2015: Campaigners call for independent inquiry into Post Office Horizon IT system dispute.
- October 2015: James Arbuthnot takes Post Office IT fight to House of Lords.
- November 2015: The union that represents Post Office subpostmasters has warned of a problem with the Horizon accounting system.
- November 2015: An email from Post Office IT support reveals a problem with the Horizon system and supporting processes that could lead to accounting errors.
- November 2015: Group litigation against Post Office being prepared in Horizon dispute.
- February 2016: Post Office faces group litigation over Horizon IT as subpostmasters fund class action.
- June 2016: Post Office chairman Tim Parker says there would be “considerable risk” associated with changing its Horizon computer system.
- November 2016: The legal team hired by a group of subpostmasters will take their case to the next stage.
- January 2017: The group action against the Post Office that alleges subpostmasters have been wrongly punished for accounting errors gets green light from the High Court of Justice.
- March 2017: 1,000 subpostmasters apply to join IT-related group litigation against Post Office.
- April 2017: Investigation into claims of miscarriages of justice in relation to a Post Office accounting system has appointed a forensic accountant firm.
- May 2017: Hundreds of subpostmasters have applied to join IT-related legal action since March.
- July 2017: Post Office defence in computer system legal case due this week.
- August 2017: Campaigners submit initial evidence in group litigation against Post Office over controversial Horizon IT system.
- October 2017: Subpostmasters’ group action against the Post Office reaches an important milestone.
- November 2017: An end is in sight for subpostmasters’ campaign against alleged wrongful prosecution, which they blame on a faulty computer system.
- November 2017: The High Court judge managing the subpostmasters versus Post Office legal case over an allegedly faulty computer system tells legal teams to cooperate.
- January 2018: Forensic investigation into Post Office IT system at centre of legal case nears completion.
- April 2018: Criminal Cases Review Commission forensic examination of the IT system at the centre of a legal case against the Post Office has raised further questions.
- May 2018: Post Office branches unable to connect to Horizon computer system for several hours after morning opening time.
- October 2018: After over a decade of controversy, next week marks the beginning of a court battle between subpostmasters and the Post Office.
- November 2018: Case against Post Office in relation to allegedly faulty computer system begins in High Court.
- November 2018: High Court case in which subpostmasters are suing the Post Office has revealed a known problem with a computer system at the core of the dispute.
- November 2018: A High Court trial, where subpostmasters are suing the Post Office for damages caused by an allegedly faulty IT system, ends second week.
- November 2018: Post Office director admits to Horizon errors and not sharing details with subpostmaster network.
- November 2018: The High Court trial in which subpostmasters are suing the Post Office has reached an important stage.
- December 2018: CCRC may hold off subpostmaster decision until after Post Office Horizon trial.
- December 2018: Court case where subpostmasters are suing the Post Office set to span at least four trials and extend into 2020.
- January 2019: Subpostmasters’ campaign group attacks Post Office CEO Paula Vennells’ New Year honour amid ongoing court case.
- January 2019: Thousands of known errors on controversial Post Office computer system to be revealed.
- March 2019: Tech under spotlight at High Court in second subpostmasters versus Post Office trial.
- March 2019: Post Office considered Horizon IT system “high-risk”, court told.
- March 2019: CCRC watching Post Office Horizon trial closely.
- March 2019: Judge rules that Post Office showed “oppressive behaviour” in response to claimants accused of accounting errors they blamed on Horizon IT system.
- March 2019: Post Office “lacked humanity” in the treatment of subpostmasters, says peer.
- March 2019: A High Court judge heard that the Post Office did not investigate a computer system error that could cause losses, despite being offered evidence.
- March 2019: The Post Office legal team in the case brought by more than 500 subpostmasters has called for the judge to be recused after questioning his impartiality.
- March 2019: A senior civil servant asked the Post Office to repay public money it had wrongly allocated to paying legal costs.
- April 2019: Subpostmaster claimants’ legal team makes application for the Post Office to pay millions of pounds of costs associated with trial.
- April 2019: Post Office to appeal judgment from first Horizon trial.
- April 2019: The Post Office’s claim that the judge overseeing the case concerning its controversial Horizon IT system was biased has been dismissed.
- April 2019: MP questions government over Post Office Horizon case.
- April 2019: Government says no conflict of interest in trial despite Post Office chairman’s dual role.
- May 2019: The Court of Appeal has refused the Post Office’s application to appeal a major decision in the Horizon IT trial.
- May 2019: The Post Office has applied for permission to appeal judgments from the first trial in its IT-related legal battle with subpostmasters.
- May 2019: The judge in the Post Office Horizon trial has ordered the organisation to pay the legal costs of its courtroom adversaries, and refused to give permission to appeal a major judgment.
- June 2019: Post Office asks Court of Appeal for permission to appeal judgment in first Horizon trial.
- July 2019: The Post Office has admitted that some subpostmasters are at risk of accounts not balancing due to an error it does not understand.
- July 2019: Problem revealed during High Court trial left subpostmaster with £18,000 surplus after IT system failed to register full amount of cash scanned in.
- August 2019: Subpostmasters suffering slow running and frozen terminals while Post Office searches for a fix to issues apparently caused by a software update.
- August 2019: The Post Office has fixed the latest problems with its Horizon system, affecting hundreds of branches.
- October 2019: A High Court judgment for a trial that focused on the Post Office’s IT system at the centre of a multimillion-pound litigation will be announced early next month.
- November 2019: The Court of Appeal has rejected a Post Office application to appeal judgments made in its multimillion-pound battle with subpostmasters over IT system failures.
- November 2019: Peer calls for clear-out of Post Office board after Court of Appeal confirms major court defeat.
- December 2019: The Post Office has settled its long-running legal dispute with subpostmasters, and will pay £57.75m in damages.
- December 2019: Subpostmansters ended their legal battle with the Post Office at the optimal time, according to the lawyer that managed the High Court action.
- December 2019: Subpostmansters proved right on IT system failures as calls for full public inquiry mount.
- December 2019: Criminal Courts Review Commission to review Horizon judgment “swiftly”.
- December 2019: National Federation of Subpostmasters cries foul after court ruling on controversial computer system.
- December 2019: Former Post Office CEO apologises to subpostmasters over Horizon scandal.
- December 2019: Call for former Post Office CEO to step down from public roles after IT court battle lost.
- January 2020: Fujitsu must face scrutiny following Post Office Horizon trial judgment.
- January 2020: Subpostmaster group calls for government to pay legal costs for Horizon trial.
- January 2020: Why subpostmasters are calling on the government to pay Horizon trial costs.
- January 2020: Department for Business, Energy & Industrial Strategy says it did not make decisions in the Post Office’s recent court battle.
- January 2020: Government should not be allowed to dismiss subpostmasters’ claims over Horizon IT scandal.
- January 2020: Police sent information about potential Fujitsu staff perjury in subpostmaster prosecutions.
- January 2020: Prosecutions are a significant step closer to being sent to the Court of Appeal as Criminal Courts Review Commission forms a group of commissioners to review them.
- January 2020: Alan Bates: The “details man” the Post Office paid the price for ignoring.
- February 2020: The government has refused to pay the huge legal costs subpostmasters incurred in their battle with the government-owned Post Office, which they won.
- February 2020: Members of Parliament seeking a public inquiry into the Post Office Horizon scandal face huge challenges, but pressure and time could force justice.
- February 2020: Calls for inquiry into Post Office IT scandal increase in Parliament, with cross-party support.
- February 2020: Care Quality Commission to review concerns over Paula Vennells’ appointment after they were raised by a former NHS consultant psychiatrist.
- February 2020: Government admits it was too passive managing Post Office as parliamentary pressure builds.
- February 2020: Minister says Post Office IT experts misled the government when it asked questions about subpostmasters’ concerns over Horizon IT system.
- March 2020: Boris Johnson commits to “getting to the bottom of” Post Office Horizon IT scandal.
- March 2020: Boris Johnson’s commitment to inquiry into Post Office scandal in doubt.
- March 2020: MPs call on PM to commit to full public inquiry into Post Office Horizon IT scandal.
- March 2020: Those who did not play by the rules in Post Office Horizon scandal “should face prosecution”.
- March 2020: MPs told to hold to account those responsible for Post Office Horizon IT scandal.
- March 2020: The Post Office has sparked anger with secret settlements with subpostmasters outside the recent legal action against it.
- March 2020: Labour MP Karl Turner tells Computer Weekly that the Post Office Horizon scandal is the most grotesque version of predatory capitalism he has ever seen.
- March 2020: MP Kevan Jones has warned a government minister not to repeat the mistakes of predecessors in relation to the Post Office Horizon IT scandal.
- March 2020: Criminal Cases Review Commission to use Microsoft Teams to ensure review of subpostmaster prosecutions is held on time.
- March 2020: Post Office postpones subpostmaster compensation scheme amid Covid-19 crisis.
- March 2020: Meeting reviewing subpostmaster applications to appeal criminal prosecutions moves into second day.
- March 2020: Subpostmaster prosecutions to be considered by Court of Appeal for miscarriages of justice.
- March 2020: How subpostmasters made legal history with biggest referral of potential miscarriages of justice.
- April 2020: Met Police examines information about evidence given in court by Fujitsu staff on the Horizon IT system.
- May 2020: Subpostmasters who had their lives ruined by the Post Office’s faulty IT system have received their damages after a High Court victory.
- May 2020: A senior Post Office executive at the centre of an IT scandal, who tried to mislead a High Court judge in relation to it, has left the organisation without fanfare despite many years of service.
- May 2020: Post Office re-examines hundreds of prosecutions that could have resulted from faults in Horizon IT system.
- June 2020: A campaign group representing subpostmasters wrongly prosecuted for theft and false accounting by the Post Office is raising money to help clear the names of victims of the scandal.
- June 2020: Subpostmasters to force scrutiny of government’s role in Post Office IT scandal.
- June 2020: The Criminal Cases Review Commission sends 47 more subpostmaster cases to Court of Appeal and asks government to review private prosecution powers.
- June 2020: Select committee chair writes to former Post Office CEO demanding answers over her role in IT scandal.
- June 2020: The government has been accused of launching a review that fails in getting to the bottom of one of the biggest miscarriages of justice in UK history.
- June 2020: Subpostmasters will not cooperate with government review into IT scandal.
- June 2020: The government’s proposed review of the Post Office IT scandal has received a further setback as forensic accountants join subpostmasters in refusing to back it.
- June 2020: Call for government review of Post Office Horizon scandal to have the power to force individuals to give evidence under oath.
- June 2020: Subpostmasters seeking justice in the Post Office Horizon IT scandal are regaining momentum in Parliament.
- June 2020: Healthcare regulator will be discussing concerns about former NHS boss chairing an NHS trust at an upcoming meeting.
- June 2020: Second Sight is working with law firm in appeals by subpostmasters against criminal convictions in Horizon IT scandal.
- June 2020: Post Office and Fujitsu blame each other for many of the failings in the Horizon IT scandal that wrecked lives.
- June 2020: Parliamentary Justice Committee to hold short inquiry into the rules and regulations surrounding private organisations’ ability to initiate criminal proceedings.
- July 2020: Victims of the Post Office Horizon IT scandal need to raise thousands of pounds in a week or those responsible for their suffering will avoid scrutiny.
- July 2020: The government is set to face scrutiny over its involvement in the Post Office Horizon IT scandal, described as one of the biggest miscarriages of justice in modern UK history.
- September 2020: The government repeats that it won’t pay victims’ legal costs and confirms review into the scandal will not have the power to call witnesses.
- September 2020: Subpostmasters still not being told about all the known errors in the controversial Post Office branch accounting and retail system that they use.
- October 2020: The Post Office has chosen not to contest 44 out of 47 appeals, meaning most are likely to have their names cleared, but others still face a Court of Appeal battle for justice.
- October 2020: MPs are demanding the government holds a full statutory public inquiry into the Post Office IT scandal.
- October 2020: NHS regulator continues enquiries about the appointment of former Post Office CEO at Imperial College Healthcare NHS Trust as more damning details emerge.
- October 2020: Government minister met with former subpostmaster online in an attempt to get victims of the Post Office Horizon scandal involved in government review.
- October 2020: The Post Office is focusing urgently on fixing an IT error suffered by a subpostmaster amid the ongoing IT scandal.
- October 2020: Labour politicians are calling for the government to give the Post Office Horizon scandal inquiry the power to force witnesses to give evidence if they don’t cooperate.
- October 2020: Imperial College Healthcare NHS Trust has asked for external review of its process when appointing controversial executive.
- November 2020: Government faces scrutiny of its handling of the Post Office IT scandal that destroyed subpostmasters’ lives and livelihoods.
- November 2020: Post Office branches offline during busy business hours after suffering an IT error that the Post Office said related to IT from supplier Fujitsu.
- November 2020: Fujitsu is refusing to explain what caused a national system outage in Post Office branches last week, despite the Post Office confirming the issue was the fault of the supplier.
- November 2020: The Metropolitan Police opens criminal investigation into Fujitsu staff who gave evidence in trials of subpostmasters wrongly prosecuted and even imprisoned for financial crimes.
- November 2020: Post Office criticised over vagueness of its explanation of the cause of a UK-wide IT failure that saw subpostmasters unable to do business.
- November 2020: Post Office says planned firmware update caused the problem that left branches unable to do business for 90 minutes.
- November 2020: Court documents reveal the names of the Fujitsu employees under investigation for potentially providing misleading information in criminal trials.
- November 2020: The government allowed the Post Office to ‘run amok’ and destroy lives, says complaint to Parliamentary Ombudsman.
- November 2020: Campaigning politician demands access to documents that could prove that the Post Office lied.
- December 2020: Government denies responsibility for the abuse inflicted on subpostmasters by the Post Office over faulty IT system.
- December 2020: CEO at the centre of the scandal that saw innocent people bankrupted and some sent to prison steps down from NHS role as pressure for her resignation grows.
- December 2020: History made as subpostmasters wrongly prosecuted in Horizon IT scandal have convictions quashed.
- December 2020: The appointment of a former Post Office executive, who tried to mislead a judge, in the Football Association of Wales has been questioned by an MP.
- December 2020: Court of Appeal indicates subpostmasters can pursue appeal route that could do more damage to Post Office’s reputation.
- January 2021: NHS trust defends its director appointment process following an external review of its recruitment of former Post Office CEO Paula Vennells.
- January 2021: Lawyers call for changes to digital evidence rule that made it easier for the Post Office to ‘bamboozle courts’ and make subpostmasters pay a heavy price for its IT failings.
- January 2021: The Criminal Cases Review Commission (CCRC) has referred four more subpostmasters’ criminal convictions to appeal, as part of the biggest miscarriage of justice in modern UK history.
- February 2021: A former senior developer who worked for Fujitsu on the Post Office IT system that led to subpostmasters being falsely accused of fraud, has claimed bosses knew of fundamental flaws before going live.
- February 2021: Subpostmasters call for Boris Johnson to pause and reshape the government’s Horizon inquiry.
- February 2021: Vote of no confidence in Football Association of Wales boss triggered by recruitment of former Post Office executive who tried to mislead a judge in IT trial.
- March 2021: Government agrees to change private prosecution rules that were abused by the Post Office in its pursuit of subpostmasters wrongly accused of financial crimes.
- March 2021: Subpostmaster victims who have spent millions bringing the Post Office IT scandal to light have received no reply to their concerns from Boris Johnson.
- March 2021: MP condemns department’s ‘bizarre’ rejection of freedom of information request linked to Post Office IT scandal.
- March 2021: Football Association Wales boss steps down after losing confidence motion triggered by appointment of an executive involved in the Post Office IT scandal.
- March 2021: The Scottish Criminal Cases Review Commission (SCCRC) is reviewing five cases of potential miscarriage of justice in relation to subpostmaster prosecutions.
- March 2021: Subpostmasters heading to Court of Appeal to clear their names in what is potentially the biggest miscarriage of justice in English legal history.
- March 2021: The Post Office does not have enough money to pay compensation to the subpostmasters it wrongfully prosecuted.
- March 2021: Angela van den Bogerd has left her role at the Football Association of Wales, following criticism of her part in Post Office IT scandal.
- March 2021: Court of Appeal hearing reveals Post Office instructed employees to destroy documents that undermined an insistence that its Horizon computer system was robust.
- March 2021: The Post Office was warned that a former Fujitsu employee had misled courts when giving evidence on its behalf.
- March 2021: Boris Johnson agrees with MP that those responsible for the Post Office Horizon scandal should be brought to book.
- March 2021: Former Post Office chief was paid over £400,000 when she left despite the organisation being involved in what would become the biggest miscarriage of justice in UK history.
- April 2021: The UK government faces a potential judicial review over its Post Office Horizon IT scandal inquiry, after subpostmasters formally wrote to the government seeking one.
- April 2021: The government is listening to calls for changes in how digital evidence is considered in court, as Post Office IT scandal spells out current rule’s inadequacy.
- April 2021: The Post Office's controversial contract with Fujitsu has been extended another year to help the organisation manage its exit.
- April 2021: The Post Office is to move work done by Fujitsu in-house when its outsourcing contract ends, and is already recruiting IT experts.
- April 2021: The Post Office has revealed the end to its controversial Horizon IT system which, through its errors and the Post Office's denial of them, caused huge suffering.
- April 2021: The UK government is the only block to fair compensation for subpostmasters who were wrongly punished for accounting shortfalls.
- April 2021: The Court of Appeal has overturned the criminal convictions of 39 subpostmasters who were blamed and punished for accounting shortfalls caused by computer errors.
- April 2021: Former Post Office CEO Paula Vennells has left roles in the church, Morrisons and Dunelm after postmasters’ convictions were overturned in the Court of Appeal.
- April 2021: The biggest miscarriage of justice in UK history is set to get bigger as more subpostmasters take their cases to the Court of Appeal.
- May 2021: Post Office IT scandal CEO has no excuse for her inaction in preventing the biggest miscarriage of justice in UK history, says Criminal Cases Review Commission chairperson.
- May 2021: Subpostmasters, MPs and the public call for a full statutory judge-led public inquiry into the Post Office Horizon scandal, following another damning court judgment.
- May 2021: Government says it wants to ensure a fair pay-out for the 555 subpostmasters who defeated the Post Office in a legal battle.
- May 2021: The Post Office has contacted hundreds of people it might have wrongly prosecuted for financial crimes.
- May 2021: The miscarriages of justice involving subpostmasters are the most disturbing element of the Post Office Horizon scandal – but it goes much deeper.
- May 2021: The supplier at the centre of the Post Office Horizon scandal has so far escaped the ramifications of its role in the biggest miscarriage of justice in UK history.
- May 2021: Another two former subpostmasters have had their convictions for financial crimes overturned, following a hearing in Southwark Crown Court.
- May 2021: The government inquiry into the Post Office Horizon scandal is set to be made statutory with the power to compel witnesses and evidence.
- May 2021: The government confirmed that the inquiry into the Post Office Horizon IT scandal will be given statutory status and wider scope.
- May 2021: The Justice for Subpostmasters Alliance has agreed to meet the former judge heading up the inquiry into the Post Office scandal that ruined the lives of hundreds of subpostmasters.
- May 2021: Criminal Cases Review Commission will not allow pressure on its resources to prevent subpostmasters seeking a review of their criminal convictions.
- May 2021: Professional IT body wants changes to how computer evidence is used in court in the wake of the Post Office case.
- June 2021: The Post Office Horizon scandal inquiry begins with subpostmaster campaign group waiting for full details before committing its support.
- June 2021: Whatever the Post Office told government about its decision to sack investigators examining subpostmaster prosecutions for theft could identify if the government was part of a cover-up.
- June 2021: The Post Office has so far compensated about 400 subpostmasters who suffered losses as a result of computer errors that they were wrongly blamed for.
- July 2021: Another 10 subpostmasters are set to have their criminal convictions quashed as part of one of the biggest miscarriage of justice in British history.
- July 2021: The government has made no contact with subpostmasters two months after it said it would work with them to ensure they get speedy and fair compensation.
- July 2021: The cost of a scheme set up to compensate subpostmasters who were victims of the Horizon IT scandal will exceed £300m.
- July 2021: The government will pay interim compensation within weeks to subpostmasters who were wrongly convicted of crimes due to computer errors.
- August 2021: A further four subpostmasters are set to have their wrongful convictions overturned in the latest development in the Post Office Horizon scandal.
- August 2021: The government has failed to provide fair compensation to the subpostmasters who exposed the full extent of the Horizon scandal to the world.
- August 2021: Subpostmasters demand more clarity on Horizon public inquiry before committing their support.
- September 2021: Six more subpostmaster convictions referred for appeal in Post Office IT scandal.
- September 2021: Government minister holds secret meeting with Post Office Horizon scandal victims.
- October 2021: The public inquiry into a scandal that saw subpostmasters imprisoned after being blamed for accounting shortfalls will hold its first public hearing early next month.
- October 2021: A government minister investigating the controversial Horizon IT project in 2000 described the Post Office board of directors as ‘appalling, short-sighted and partisan’.
- November 2021: The behaviour of Post Office senior management during the Horizon scandal was so egregious that the supplier of the faulty software has escaped a large financial penalty.
- November 2021: Former Fujitsu staff who gave evidence in subpostmaster trials have been questioned by police for a second time.
- November 2021: Former subpostmasters convicted of crimes based on data from error-prone Post Office computer system continue to embark on appeals.
- November 2021: The first hearing in the Post Office Horizon scandal public inquiry hears why victims should be paid compensation immediately.
- November 2021:The Scottish Criminal Cases Review Commission is investigating eight potential miscarriages of justice linked with faulty Post Office IT system.
- November 2021: The Post Office will waive professional legal privilege for documents relating to legal advice it received regarding subpostmaster prosecutions.
- November 2021 A total number of 65 subpostmasters have now had criminal convictions overturned in Post Office Horizon scandal.
- November 2021 Subpostmasters asked to withdraw support for Post Office scandal inquiry.
- November 2021: Seven more subpostmasters have been cleared after the Post Office charged them for crimes caused by its faulty Horizon software.
- November 2021: The Post Office made clear its support for a change in UK law regarding computer evidence that was making prosecution ‘onerous’ – a change which later helped to wrongfully convict subpostmasters.
- November 2021: The chair of the Post Office scandal public inquiry has confirmed the compensation of a group of subpostmasters will be revisited.
- December 2021: Government must go further after agreeing to pay compensation for wrongly convicted subpostmasters.
- December 2021: Pressure on government to pay fair compensation to subpostmasters left out of current schemes.
- January 2022: Almost 100 MPs have backed a call for the government to reverse its decision to exclude 555 subpostmasters from fair compensation.
- January 2022: A parliamentary select committee was told that the Post Office is unable to access information to accurately calculate compensation for some Horizon scandal victims.
- January 2022: The Post Office received subsidies worth over £1bn last year, including a £685m payment just last month, in a scheme labelled Post Office Historical Matters Compensation.
- January 2022: Government widens subpostmaster miscarriage of justice compensation scheme in Horizon scandal.
- January 2022: Government officials are open to finding a way to properly compensate victims of the Horizon scandal without setting a dangerous legal precedent.
- January 2022: The subpostmaster campaign group responsible for exposing the Post Office Horizon scandal is to meet with the government to discuss fair compensation for their suffering.
- January 2022: Fujitsu cannot hide away as taxpayers pick up the bill for the Post Office scandal triggered by its IT system, say peers.
- February 2022: Victims of the Post Office Horizon scandal are being denied the millions of pounds they are owed as the government delays compensation resolution.
- February 2022: Victims of the Post Office Horizon scandal are due to tell their devastating stories to the statutory inquiry.
- February 2022: MPs are demanding urgent action by the government to provide full compensation to a group of 555 Post Office Horizon scandal victims who have so far been left out.
- February 2022: Victims of the Post Office Horizon scandal have been suffering in silence for many years, but the current public inquiry is giving them a voice, and people are listening.
- February 2022: Horizon inquiry questioning raises hopes of fair compensation for victims so far left out.
- February 2022: Government set to backtrack on untenable position on subpostmaster compensation.
- March 2022: The Post Office and Fujitsu failed to alert subpostmasters to a software error that caused them to be wrongly blamed for accounting shortfalls.
- March 2022: Horizon inquiry hearing sheds light on subpostmaster federation’s role in hushing up IT problems.
- March 2022: 555 subpostmasters to get fair compensation after government U-turn on its stance on High Court settlement.
- March 2022: Compensation goal finally in sight for 555 Post Office scandal victims, after 13 year campaign.
- April 2022: Fujitsu bags £430m government contracts despite rising cost of Post Office Horizon scandal.
- April 2022: The Scottish Criminal Cases Review Commission expects more subpostmasters with potential wrongful convictions to come forward.
- April 2022: Former subpostmasters who were wrongfully convicted and punished for crimes have not yet received full compensation over a year after their convictions were overturned.
- April 2022: A former Fujitsu worker has been questioned under caution for the third time as police investigate potential perjury in trials of subpostmasters wrongfully convicted of financial crimes.
- May 2022: Paula Vennells could be stripped of her CBE as the Honours Forfeiture Committee commits to reconsider its award in the light of the Post Office Horizon scandal.
- May 2022: Lawyer negotiating compensation for victims of Post Office scandal says the two sides are ‘poles apart’ on valuations.
- May 2022: Inquiry into Post Office scandal moves to Scotland, with differences in English and Scottish law raising further serious questions about subpostmaster prosecutions.
- May 2022: The chair of the Post Office Horizon scandal inquiry has brought forward hearings about compensation as victims warn that at this rate “people will die” before they get anything.
- May 2022: The Criminal Cases Review Commission is to contact 88 more potentially wrongfully convicted Post Office workers.
- May 2022: The Post Office Horizon IT system at the centre of a national scandal will be replaced by 2025, with a supplier expected to be named in August.
- May 2022: Victims of the Post Office Horizon scandal in Scotland raise further questions about Post Office and government conduct.
- May 2022: Government accused of ‘passing the buck’ and ‘not knowing what it is talking about’ after stating it has no plans to review court rules on computer evidence.
- May 2022: Computer Weekly spoke to the barristers at Henderson Chambers that fought the Post Office in the High Court to expose the widest miscarriage of justice in UK history.
- June 2022: Two more Post Office Horizon scandal victims have had their wrongful convictions overturned.
- June 2022: The 555 subpostmasters who exposed the depth of the Post Office Horizon scandal could finally be fairly compensated.
- June 2022: Forensic accounting firm that ‘knows where the bodies are buried’ will be released from confidentiality obligations by the Post Office to give evidence to public inquiry.
- June 2022: Lawyers negotiating the compensation valuations for former subpostmasters who suffered wrongful convictions have brought in independent judicial scrutiny to break an impasse.
- June 2022: Subpostmaster campaign group is a step closer to achieving what it was originally set up to do as government launches compensation scheme for its members who did not receive fair payouts.
- July 2022: More former subpostmasters have their wrongful convictions for theft and fraud overturned in the Court of Appeal.
- July 2022: When the Post Office’s lie about the Horizon system failed to silence subpostmaster critics, it took more extreme measures, say victims of the scandal.
- September 2022: The Met Police have interviewed a former subpostmaster as part of an investigation into potential perjury by former Fujitsu staff.
- September 2022: Chair of statutory public inquiry into the Post Office Horizon scandal has aired his disappointment over the slow progress in making interim payments to victims.
- October 2022: The public inquiry into the Post Office scandal has begun phase two with a request for adjournment amid allegations that the Post Office is failing to disclose relevant documents.
- October 2022: Victims demand that the perpetrators of the Post Office Horizon IT scandal face the public inquiry.
- October 2022: Fujitsu’s part in causing the extreme suffering of subpostmasters will be made clear as the IT supplier begins giving evidence at a statutory inquiry.
- October 2022: A dereliction of duty saw subpostmaster federation ignore its members when IT problems hit and allowed the Post Office destroy their lives.
- October 2022: Politicians are keeping up the pressure to block government contracts being awarded to Fujitsu because of its role in the Post Office Horizon scandal.
- October 2022: Problems reported with the Post Office’s Horizon IT system before its roll-out should have been regarded as a “show-stopper.”
- October 2022: Horizon system code writers lacked basic programming skills, according to the task force set up to investigate reported problems with the controversial software.
- October 2022: Trials of the Horizon computer system in Post Office branches in 1999 led to a warning from subpostmasters that software problems meant “a tragedy was not far away”.
- November 2022: ‘Hardball’ negotiations between the government, the Post Office and ICL meant subpostmasters were ignored and thrown into a tragedy that could have been averted.
- November 2022: Post Office investigators were so convinced that subpostmasters were cooking the books that they failed to investigate alleged IT problems, a public inquiry has been told.
- November 2022: SCCRC has referred six cases of potential wrongful convictions of subpostmasters to the High Court of Justiciary.
- November 2022: A former Fujitsu technology expert who defended the Horizon system’s robustness in court was unhappy after being ‘manoeuvred’ into acting as an expert witness.
- November 2022: Insider tells public inquiry that the Post Office continued to roll out the controversial Horizon system despite a ‘considerable’ number of errors, because it was too committed.
- November 2022: Former members of the ICL team developing software for the Post Office Horizon EPOSS system were unqualified and engaged in poor software development practices.
- November 2022: The Post Office IT scandal inquiry’s appointed expert IT witness was “troubled” by the lack of integrity of data from the Horizon system that was used to send people to prison.
- November 2022: Telegram from British Embassy in Tokyo to UK government reveals pressure on ministers to sign off controversial contract.
- November 2022: The National Federation of Subpostmasters (NFSP) deliberately kept stories of Horizon errors quiet because it “did not want to kill the project”.
- December 2022: The Post Office was ‘keen’ to make subpostmasters cover unexplained accounting shortfall as its business struggled, public inquiry hears.
- December 2022: The second phase of the Post Office Horizon IT scandal raised more questions over who did what, when and where, with shocking revelations at every turn.
- December 2022: The Criminal Cases Review Commission wants former subpostmasters to come forward if they think they were prosecuted by the Post Office based on data from the Horizon computer system.
- January 2023: Alan Bates, who fought for decades to expose the Post Office Horizon IT scandal, says it would be inappropriate to accept an OBE when former Post Office CEO still holds her CBE.
- January 2023: The advisory board set up to oversee compensation awards to 555 victims of the Post Office Horizon scandal has agreed a goal of returning them to the financial position they would have been in had the scandal not happened.
- January 2023: Two former Fujitsu workers, who are currently under police investigation for possible perjury, will give evidence and face questions in Post Office inquiry.
- February 2023: The Post Office messaging strategy was designed to reassure staff that the Horizon accounting system was robust after Computer Weekly first revealed problems in 2009.
- March 2023: Post Office attempted to replace controversial Horizon system 10 years ago, but was put off by project’s scale and cost.
- March 2023: IT worker tells public inquiry that the Post Office Horizon helpdesk was toxic, rudderless and racist.
- March 2023: One Post Office scandal victim was deliberately destroyed by the Post Office to deter other subpostmasters from challenging the integrity of its core computer system.
- April 2023: The CCRC has told former Post Office workers the door is still open for them to come forward if they were prosecuted for financial crimes based on evidence from Horizon software.
- April 2023: The Post Office has extended a contract with Fujitsu after being unable to resolve technical issues related to migrating its IT to the cloud.
- April 2023: The Post Office ended a proposed contract with IBM to replace its controversial Horizon system after work had already started.
- May 2023: A total of 86 former subpostmasters wrongly prosecuted for financial crimes after computer errors showed phantom losses have had convictions overturned.
- May 2023: Fujitsu had no control over staff in one of its tech support teams accessing Post Office branch accounts remotely to make changes which could be hidden from subpostmasters.
- May 2023: An email has revealed that a senior Post Office lawyer bragged about how his team successfully prosecuted a subpostmaster for theft, sending her to prison while pregnant.
- May 2023: A 2010 Post Office internal review of the Horizon software was designed to ignore the system’s problems to reassure stakeholders amid questioning of its reliability.
- May 2023: The man who exposed the Post Office scandal fears a long delay for victims due to compensation process being ‘bogged down by bureaucracy’.
- May 2023: Third phase of public inquiry into Horizon IT scandal reveals extent of Post Office and Fujitsu cover-up of software problems that went on to write ‘as dark a chapter in our governmental, corporate and legal history as can be imagined’.
- June 2023: Post Office CEO told MPs that the organisation is telling some subpostmasters it won't oppose them if they appeal.
- July 2023: The Post Office told investigators to include potential evidence in reports to their own lawyers, but not the subpostmasters they suspected of theft.
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