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The Post Office Horizon IT scandal: convictions quashed but the legal causes remain

In a previous article in the Newsletter, “The Post Office Horizon scandal: the law says computers are reliable”, I set out an outline of the facts leading up to the second trial against the Post Office by Justice for Subpostmasters Alliance set up by Sir Alan Bates, recently and deservedly appointed a Knight Batchelor in the King’s 2024 Birthday Honours List.

This article considers the legislation that has now been passed in both the UK and Scottish Parliaments, quashing all convictions relating to sub-postmasters and sub-postmistresses. However, there is a problem: the new laws do not address the reasons why the Post Office Horizon IT scandal occurred.

The article sets out the legislation in brief, highlights the main controversy, and ends by pointing out that the causes of the scandal remain.

The lead-up to the legislation

The slow pace of dealing with appeals and providing for compensation over the Post Office Horizon IT scandal escalated dramatically and rapidly after the broadcast of a four-part British television drama series for ITV, “Mr Bates vs The Post Office” in January 2024. As a direct result of this dramatization of reality, the Prime Minister Rishi Sunak announced the introduction of primary legislation to overturn the wrongful convictions of hundreds of sub-postmasters and sub-postmistresses. Following the decision to call a general election, which meant Parliament was dissolved on Thursday 30 May 2024, the Post Office (Horizon System) Offences Act 2024 was passed under the fast-track procedure known as the “wash-up”. The Act extends to England and Wales and Northern Ireland and entered into force on the day on which it passed (s11).

The lead-up to the passing of the legislation included a number of papers and reports:

The passing of the Act included an Open letter to postmasters, providing an outline of the provisions of the Act and explaining how to claim financial redress, which is provided for in the Post Office (Horizon System) Compensation Act 2024. The Post Office also maintain a section on its corporate website, “Overturned Convictions and Compensation: Information on Progress”.

A separate item of legislation was considered by the Scottish Parliament. The Post Office (Horizon System) Offences (Scotland) Act 2024 has now been enacted. There are useful supporting documents by Frazer McCallum.

This article considers the legislation applicable to England & Wales and Northern Ireland.

The purpose of the Act

Paragraph 1 of the Explanatory Notes to the Act set out the purpose of the Act:

“The Post Office (Horizon System) Offences Act 2024 will quash the convictions of sub-postmasters and others who worked, including on a voluntary basis, in post office branches (all referred to below as “postmasters”) who have suffered as a consequence of the Post Office Horizon IT scandal. It will quash, on a blanket basis, convictions for various theft, fraud and related offences during the period of the Horizon scandal in England and Wales.”

The quashing of convictions for relevant offences

Section 1 provides for the quashing of convictions for relevant offences. The Act provides that every conviction to which the Act applies is quashed.

Where a person was prosecuted and convicted in England and Wales, the Act applies where the conviction took place before the Act came into force, when the offence was prosecuted by the Post Office or the Crown Prosecution Service, and the conviction has not been considered by the Court of Appeal in England and Wales.

For those prosecuted and convicted in Northern Ireland, the Act applies where the conviction took place before the Act came into force, when the offence was prosecuted by the Police Service of Northern Ireland, the Director of Public Prosecutions for Northern Ireland or the Public Prosecution Service for Northern Ireland, and the conviction has not been considered by the Court of Appeal in Northern Ireland.

The meaning of a “relevant offence”

The meaning of a “relevant offence” is set out in section 2. For a “relevant offence” to be within the meaning of the Act, five conditions (A–E) have to be met (ss 2–6). They are:

  • The offence was alleged to have been committed between 23 September 1996 and 31 December 2018.
  • The offences charged must be false accounting, fraud, handling stolen goods, money laundering, theft, or an ancillary offence relating to any of these offences.
  • At the time of the alleged offence, the person must have been carrying on a post office business or was working in a post office.
  • The person prosecuted was carrying on, or working for the purposes of, the post office business.
  • At the time of the alleged offence, the Horizon system was being used for the purposes of the post office business.

A number of appeals of sub-postmasters and sub-postmistresses had already been heard by Crown Courts (where a conviction occurred in a Magistrates’ Court) and the Court of Appeal. The government considered that where appeals were not successful, the appellants did not come within the provisions of the Act. Section 3 sets out the criteria to determine when a conviction has been considered by the Court of Appeal. A conviction has been considered by the Court of Appeal only if:

  • the Court of Appeal has dismissed an appeal against the conviction;
  • the Court of Appeal has refused to give leave to appeal against the conviction;
  • a single judge of the Court of Appeal has refused to give leave to appeal against the conviction, and the Court of Appeal has not subsequently given leave to appeal against the conviction.

The main controversy

Of concern were those sub-postmasters and sub-postmistresses whose appeals were not successful. In this respect, subsection 5 applies, in that the Act does not prevent a further appeal against a conviction that has been considered by the Court of Appeal. This particular matter was commented upon by the members of the House of Lords Select Committee on the Constitution in their Report “Post Office (Horizon System) Offences Bill, 6th Report of Session 2023–24” (HL Paper 126, 24 May 2024). The members of the Committee made a number of important observations regarding the constitutionality of the Bill before it was enacted. This article does not concern itself with the broader constitutional criticisms, important as they are. Of concern here is the fact that the Act does not cover those sub-postmasters and sub-postmistresses whose appeals were not successful. The members of the Committee made it clear that they considered the Act to be ill-conceived, but notwithstanding this view, the inconsistency was noted at paragraph 29:

“The House may wish to consider whether quashing convictions that have been upheld on appeal would be a further legislative incursion into the role of the courts or whether, on the grounds of consistency, the Bill should be amended to include such cases.”

This anomaly was also the subject of comment in the House of Lords debate on Thursday 23 May 2024. Lord Arbuthnot, who has had a long and honourable part in trying to get to the truth of this scandal, said:

“I take a different view about those cases that have been before the Court of Appeal. We shall, I hope, decide today in Parliament to overturn the convictions of hundreds of sub-postmasters. We need to try to be fair. as between sub-postmasters. in choosing those whose convictions we overturn. The 13 cases which have been before the Court of Appeal in one way or another are not outstandingly wicked, compared with the hundreds of other sub-postmasters whose convictions will be overturned. Those 13 will not necessarily have the recourse of going back to the Court of Appeal because there may be no new evidence in their individual cases – new evidence which other sub-postmasters whose convictions are being overturned by this Bill are not required to provide. That is not fair …”

Baroness Butler-Sloss, the first female Lord Justice of Appeal, agreed with this inconsistency:

“My Lords, I remain extremely unhappy about this Bill and the way in which it has arisen, but I recognise the overwhelming importance of, at long last, doing justice to sub-postmasters. I assume that the evidence given to the Court of Appeal would have been similar to the evidence given to the original court. In those circumstances, it seems that the noble Lord, Lord Arbuthnot, is absolutely right and they should not be treated differently.”

This matter is particularly important. To give one example, the appeal of David Cameron was refused on the grounds that it was not a Horizon case in White v Post Office Ltd [2022] EWCA Crim 435. However, when considering the comments of Simon Clarke in his first witness statement submitted to the Post Office Horizon IT Inquiry, the decision of the members of the Court of Appeal in the appeal of David Cameron is difficult to reconcile against Mr Clarke’s observations. Mr Clarke was instructed to prosecute Mrs Balvinder Samara. The facts of this case are almost identical to those alleged against David Cameron (paragraphs 17–27 of his statement). Mr Clarke was not satisfied with the evidence from the Horizon system, noting that although Gareth Jenkins told him that “he was satisfied that the integrity of Horizon was intact” (paragraph 22), he declined to prosecute once he was made aware of the Interim Review report by Second Sight Limited (pdf) (see paragraphs 26, 27, 31(b), 39 and 41).

Other provisions of the Act

The Act also provides for the identification of the convictions that are quashed (s 4) and the deletion of cautions (ss 5 and 6). The Act also provides the authority for government ministers to amend or modify that Act (ss 8 and 9), which the House of Lords Select Committee on the Constitution considered draconian and unnecessary (paragraph 33 of their Report).

The causes of the scandal have not been dealt with

The conclusions of the House of Lords Select Committee on the Constitution are well made. However, there are a number of issues that arise from this scandal that need rectifying by the legal profession.

First, there has been a lack of any speed in appeals reaching the Court of Appeal. This ought to be remedied.

Second, the legal profession must deal with the problem that it has collectively permitted lies and obfuscation to override the need for appropriate disclosure (see “Software is reliable and robust”, pp xiii–xiv) in cases where electronic evidence is central to the allegations (whether in criminal prosecutions or civil proceedings, for which see the case of Lee Castleton). There is ample advice for lawyers and judges on pertinent disclosure in relation to electronic evidence in the paper requested by the Ministry of Justice in 2020 and published in 2021 “Recommendations for the probity of computer evidence”, but the advice has been ignored.

Third, the presumption that computers are reliable must go. I spent a great deal of time researching the false premise that computers can be reliable in the lead-up to the second edition (2010) of Electronic Evidence (as it was then entitled). The presumption is dealt with in detail in the 5th edition of Electronic Evidence and Electronic Signatures. The startling fact is that it is not known how many other prosecutions will have been and are affected by the presumption. The misuse of the presumption cannot be restricted to the Post Office Horizon IT scandal. That a computer has failed may well not be obvious. Professors Ladkin, Littlewood, Thimbleby and Thomas have written eloquently about this particularly for lawyers in “The Law Commission presumption concerning the dependability of computer evidence”, and further very important articles have been written by Professor Ladkin and James Christie.

It is essential that the Law Commission revise the presumption that computers are reliable. As James Christie has demonstrated (page 62 of his recent article “The Law Commission and section 69 of the Police and Criminal Evidence Act 1984”):

“A study of the papers and articles quoted in the consultation paper and final report reveals that the Law Commission misunderstood, or misrepresented, the opinions of the main sources cited as being in favour of repeal. The Law Commission failed to address the strongest arguments against repeal without replacement, …. It ignored the advice of the experts they cited who all argued that the focus of courts should be on the reliability of computer evidence, ….. The Law Commission’s comments and conclusions revealed that they had not understood the nature of computers and complex software systems as described in the sources upon which they relied.”

Fourth, the profession needs to understand that it must educate itself and future lawyers in electronic evidence, as argued by Denise H Wong and Deveral Capps over a decade ago.

Finally, Vikram Dodd, for The Guardian, has reported that the police intend to pursue a significant criminal inquiry into those responsible for the scandal. Let us hope it succeeds, because the most striking observation to be made over this scandal is that the legal profession has signally failed to accept any responsibility for the failures.

© Stephen Mason, 2024

Stephen Mason was called to the Bar by Middle Temple in 1988 and is a Visiting Researcher (2023–2024) at the Centre for Technology, Robotics, Artificial Intelligence and the Law, National University of Singapore (although not physically in Singapore)

He is the joint editor, with Professor Daniel Seng, of Electronic Evidence and Electronic Signatures (5th edition, Institute of Advanced Legal Studies for the SAS Humanities Digital Library, School of Advanced Study, University of London, 2021), open-source.

He founded the open-source international journal Digital Evidence and Electronic Signature Law Review.

Photo by Mick Haupt on Unsplash.

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