There was never any doubt in my mind as to the civil litigation case of the year –  Bates -v- The Post Office.   All civil litigation  is here, witness and expert evidence, allegations of bias, disclosure and much more.  One can only admire the tenacity of the claimants and their lawyers.   All litigation life is here, including allegations of judicial bias. Here is a look at Bates & Ors v the Post Office Ltd (No 6: Horizon Issues) [2019] EWHC 3408 (QB).  A look at the judge’s assessment of the evidence is of considerable interest. (The case settled, with the Post Office paying damages and costs after this judgment was handed down. There are a number of cases being considered by the criminal courts. The judge referred the evidence from some of the employees of Fujitsi to the Director of Public Prosecutions).  This was litigation on an epic scale, with immense resources being used by the Post Office (four different Leading Counsel, two firms of solicitors, £13.9 million in costs – keep a close eye on the price of stamps).

“Infallibility is a rare commodity, and everyone is capable of making mistakes. However, it is how one reacts to mistakes that is telling.”

” This approach by the Post Office has amounted, in reality, to bare assertions and denials that ignore what has actually occurred… It amounts to the 21st century equivalent of maintaining that the earth is flat.”


The claimants alleged that computer software provided by the defendant was defective, this gave rise to allegations of dishonesty being made against post officer employees and, in some cases, criminal trials being brought. There had been a number of preliminary trials.  This trial was concerned with whether the software used was, in fact, defective.


There are interesting observations on the way in which the witness evidence was collected. For instance an expert called who worked for  Fujitsi – the supplied of the system. Mr Dunks.

284. Mr Dunks gave every indication, in the first part of his cross-examination, of being helpful and frank, and explained the process of data extraction and answered questions put to him openly. However, this encouraging start came to an end when he was asked about two curiously worded paragraphs in his statement. These stated as follows:
“8. There is no reason to believe that the information in this statement is inaccurate because of the improper use of the system. To the best of my knowledge and belief at all material times the system was operating properly, or if not, any respect in which it was not operating properly, or was out of operation was not such as to effect the information held within it.
  1. Any records to which I refer in my statement form part of the records relating to the business of Fujitsu Services Limited. These were compiled during the ordinary course of business from information supplied by persons who have, or may reasonably be supposed to have, personal knowledge of the matter dealt with in the information supplied, but are unlikely to have any recollection of the information or cannot be traced. As part of my duties, I have access to these records.
  1. Before I come to his evidence about this, it is obvious that the wording of paragraph 8 is almost that of a legal disclaimer (or a legally worded claim of accuracy, to be more precise), rather than a witness’ actual evidence. It would be very curious for a witness of fact to decide to put such a formally (and rather clumsily) worded paragraph in their witness statement. However, he was asked about these passages. He was asked what he meant by “the system”. The transcript records the following:
“Q: What is the “system” there?  Is that the system of the process of extracting audit data, or is it something else?
  1. Good question.  There’s no — I’m not sure what I was meaning by that, “There is no reason to believe …””
  1. He was asked if, in relation to the part which states “the system was working properly or, if not, any respect in which it was not operating properly, or was out of operation” the following:
“Q: Again, pausing there, it is slightly confusing.  Are you aware or not aware of any instances where that system was not operating properly?
  1. No, not really, no.”
  1. He was asked if that part of the statement had been written for him by someone else, and he said he could not remember. He was also asked if it was a “Fujitsu party line” to put this in statements when it comes to extracting data and he said no, and that he was not aware of a Fujitsu party line. He accepted that gaps and duplicates in audit data were problematic, and he explained that they had to be investigated by audit support. It was clear to me that Mr Dunks considered audit data that had gaps and duplicates should not, in that form, be used. He said he would contact audit support if these occurred.
  1. However, some of Mr Dunks’ evidence, in particular what he had to say about paragraph 8 of his own statement, proved in my judgment to be somewhat misleading.
  1. He was shown a witness statement from Mr Gareth Jenkins from the Misra criminal trial in 2010. He said he had not seen this statement before. The statement put to him is some 8 years older, approximately, than his own statement. Mr Jenkins’ statement stated at the end:
“There is no reason to believe that the information in this statement is inaccurate because of the improper use of the computer. To the best of my knowledge and belief at all material times the computer was operating properly, or if not, any respect in which it was not operating properly, or was out of operation was not such as to effect the information held on it. I hold a responsible position in relation to the working of the computer.”
  1. The similarities between this passage, and the one in paragraph 8 of Mr Dunks’ witness statement almost 9 years later, are somewhat striking. Given he had not seen the statement before, there was no obvious explanation. His answer was as follows:
“Q.  And you’re not sure why it would largely replicate your paragraph 8?
  1. No, I mean, we do have a standard witness statement that we produce for ARQs.  When we supply ARQs we are sometimes asked for a witness statement to go through the process and verify as far as I’m aware that the data I supplied is accurate.  Now, we use that quite a lot and it may actually be in that statement.
  2. I see.  So when I asked you earlier whether it was something of a Fujitsu party line you said you didn’t think it was, but actually it looks as though it is on the basis of what you have just told me and on this document as well.
  3. It could be.  It may be part of our standard witness statement that we supply.
  1. Mr Jenkins had given evidence in his witness statement from 2010 about duplicate entries in the audit data that had had to be removed. Mr Dunks was then taken to the witness statement of another Fujitsu witness in the Misra trial, called Penelope Thomas. She had given evidence about data extraction and listed a number of controls, which were remarkably similar to the ones that Mr Dunks gave evidence about (although Ms Thomas had omitted one). This is hardly likely to be a co-incidence, if Mr Dunks really had compiled his list of controls from memory or experience. She also had the identical passage in her witness statement as Mr Dunks’ paragraph 8.
  1. Mr Dunks also said in respect of this, which in my judgment painted a rather different picture to that portrayed in his witness statement, the following:
“A.  The statement again is to verify the integrity of the data once extracted and given.  We don’t control what’s in the data.  Our process is about extracting it and securely passing it over to the Post Office.  It’s not our concern of what’s in the data.
  1. It’s not your concern what’s in the data?
  2. No, it’s what we’re — we’re process-driven to extract certain types of data for certain requests.
  3. And so whether or not that might match another record or not, or replicate or duplicate or have gaps, that’s not part of your remit, that’s not really part of your concern?
  4. No, it’s not.
  5. I see.  So reading that and reading the paragraph 8 as it was in your witness statement, it doesn’t give much comfort to somebody that’s then trying to rely on ARQ data as being a gold standard to compare and investigate anomalies, does it?
  6. Possibly not.”
  1. The reference to “gold standard” was the expression that had been used by Dr Worden in his report to describe the quality of the audit data that was held by Fujitsu. It should be a very great concern to anyone tasked with extracting audit data, should that data prove to have gaps and duplicates in it. This is because gaps and duplicates in the data affects the accuracy of that data. I consider that such a cavalier approach to whether audit data has gaps and duplicates, as evidenced by Mr Dunks’ saying that such things were not part of his concern, to be entirely contradictory to a statement verifying the accuracy of such audit data.
  1. My findings in relation to this are as follows:
  1. Mr Dunks expressly sought to mislead me by stating that there was no “Fujitsu party line” when it came to the contents of drafting witness statements about audit records for legal proceedings. There plainly is; it was used in the Fujitsu statements in 2010 and it was used by him in his statement for the Horizon Issues trial.
  1. The passage included in paragraph 8 of his statement is plainly a standard form of words, and reads as though it is a legally drafted assertion of accuracy. The witness’ assertion that the system was at all material times working properly, or if it wasn’t, this did not affect accuracy, does not sit consistently with Mr Dunk’s acceptance of gaps and duplicates in audit data.
  1. That Mr Dunks did not really know very much about paragraph 8 of his own witness statement was confirmed by the way he was puzzled when he was asked about it.
  1. However, Mr Dunks’ acceptance of standard wording provided by others (probably within Fujitsu) is less important than the fact that he originally tried to mislead the court.
  1. I do not accept that he identified the 12 controls in his statement from his recollection. He must have been working off another document, which he was not prepared to identify. I draw this conclusion because of the marked similarity with the controls included in Mrs Thomas’ statement from 2010; the wording of the controls themselves; and the fact he was prepared to mislead me about the paragraph 8 point.
  1. In re-examination he asserted that the statements in his paragraph 8 were true, and that he would not have signed his statement had this not been the case. I find that he cannot have known whether those statements were true or not. There is no evidence of any steps he took to check whether or not they were true or not. I find they were simply standard sentences supplied to him, and I find that he signed his statement without any independent knowledge of whether they were true or not.
  1. I find that passage in his witness statement simply to be meaningless assertion.


In relation to another witness it called the Post Office attempted to explain problems with a witness it had called.
In the Post Office’s closing submissions, an explanation was given in submission in relation to the explanation given by Mr Godeseth in his witness statement which I have set out in [325] above about why the records did not exist, that explanation being that the procedure was not implemented. The Post Office submitted that it was only section 1.4 of the document that was not implemented, and not the whole document. This was in paragraph 147 of its written closing submissions, which dealt with what the Post Office submitted were “errors” made by Mr Godeseth which it submitted (and which the Post Office accepted) were “significant” and which it also stated had taken the Post Office “by surprise”. It sought to correct these errors, by way of submission rather than evidence, and one of those corrections was in relation to the implementation of the document in question. The claimants objected to this, and said the explanation that was provided was nowhere in the evidence, and the Post Office should not be permitted to give evidence by way of submissions.
  1. Leading counsel for the Post Office was asked about this specific part of the submissions at the end of oral closing submissions and said that the explanation in paragraph 147.4 of the closing was “my instructions but, my Lord, it is based upon a previous version of the document and then an amended version of the document. And I will undertake to give your Lordship the two references.” In an email of 10 July 2019, which provided some references, further explanation was given which were said to support the submission that it was only section 1.4 of the document that was not implemented. The Post Office relied upon the following four points in support of that submission:
  1. The passage in Mr Godeseth’s witness statement I have reproduced at [325] above.
  1. That there were different versions of the document that were disclosed, but only one had been put in the trial bundle. The first version containing section 1.4 was dated 6 June 2010 and was authored by Mr Salawu.
  1. This indicated therefore that the change was introduced by him. Most of the procedure document had been in existence for a number of years before that.
  1. Earlier versions had been disclosed, none of which contained section 1.4, and none included section 1.4 and none were distributed to or even mentioned Mr Salawu.
  1. The following points can be made about this.
  1. Witness statements are expected to be factually correct.
  1. Each party in this litigation who has submitted witness statements had ample opportunity to ensure those statements contain accurate evidence before they were served. Further, each witness is asked, at the beginning of their evidence when they confirm the contents of their statements in their evidence in chief. Apart from qualifications that were sometimes made, in this case (and in the great majority) the statements are usually stated to be true to the best of that witness’ knowledge and belief.
  1. If a witness’ written evidence is shown to be incorrect (as Mr Godeseth’s, along with other of the Fujitsu witnesses, was) then the appropriate way to correct this is eitherin re-examination or by way of supplementary evidence. Here, Mr Godeseth was asked about this document and gave evidence in respect thereof on 20 March 2019. Mr Parker, also a senior witness from Fujitsu, was not called to give evidence until 11 April 2019. That was, again, ample time for this self-contained point to have been dealt with by supplementary evidence from Mr Parker, if that was thought by the Post Office to be important. In any event, there is no reason for it having been incorrect in the first place. Whether a procedure was, or was not, adopted by Fujitsu internally, is not something that ought to be capable of misinterpretation in any event, let alone on a subject as important as recording problems in the Horizon system.
  1. I do not accept a matter such as this is suitable to be corrected by submission “on instruction” in any event.
  1. However, even if it were, I am afraid that my view of information emanating from Fujitsu is, based on numerous other instances of such information being wrong in the actual evidence, to be somewhat sceptical of its reliability. It would also be potentially unfair to the claimants to allow this type of “correction” as they would be deprived of the opportunity of testing the new explanation. Absent some corroboration of this type of information coming from Fujitsu that supported it, I would not accept it in this case on this issue.
  1. Further, and even if I were to take a contrary view of the points at 1 to 5 above, and accept that the Post Office should be given the opportunity of correcting Mr Godeseth’s evidence in this way, the explanation given by way of closing submissions does not assist the Post Office, for the reasons explained in the following paragraphs, [334] and [335] below.


In relation to another expert.
  Although Mr Parker agreed, as it was put to him more than once, that accuracy is important, I do not consider his evidence in his witness statements to have been remotely accurate, even though he stoutly maintained that it was. He continued to maintain this in his re-examination, even though by then he can have been in no doubt that he had departed from Fujitsu’s own definition – which he had said he had forgot about. I found him a very unsatisfactory witness, who presented in his witness statements a misleading and one-sided sanitised version of actual problems and events that Fujitsu had experienced throughout his time at SSC. Although he provided tables with one of his witness statements that provided a detailed commentary on a large number of PEAKs and KELs, that commentary appearing in a column headed “Fujistu’s Comments” with two columns, “Response to Mr Coyne” and “Financial Impact on branch accounts” – that latter almost always “no impact”. The entries in those columns are almost entirely self-serving by Fujitsu and I find them to be of no evidential value. The text of the actual PEAKs and KELs themselves are far more useful, obviously entered at a time when the Fujitsu/Post Office position in the litigation was not at the forefront of the different authors’ minds, and these are what for the most part the experts have considered. Mr Parker’s table is of no assistance.”


An important witness was not called by the Post Office.

  1. It is entirely a decision of the parties which witnesses they choose to call in any proceedings in respect of any evidence. The position of one person, however, who did not appear in the Horizon Issues trial, must be considered in more detail than would be usual, as the claimants make considerable complaint about this. The person in question is Gareth Jenkins, a senior Fujitsu employee who, although he retired recently, was obviously widely available to the Post Office and the source of a great amount of information both to the Post Office’s witnesses of fact, and also to Dr Worden (although he was not separately identified in Dr Worden’s “sources of information” paragraphs in his 1st Report). The fact that he provided information to Dr Worden emerged during the latter’s cross-examination. Mr Jenkins had previously given expert evidence for the Post Office in some of the criminal prosecutions of SPMs, in particular that of Ms Misra, to whom I have referred above, who was convicted of criminal offences in Guildford Crown Court in 2010.
  1. When the Post Office served its evidence of fact, there was no witness statement from Mr Jenkins, although many of their witnesses relied upon him as their source of information, he was referred to very often, and he obviously knew a great deal about Horizon. The extent and way in which Mr Jenkins had been closely involved was explained by Mr Godeseth in his cross-examination. Mr Godeseth had, in respect of the receipts and payments mismatch, originally stated in paragraph 42 of his 2nd witness statement that 60 branches were affected. He had corrected this to 62, a factual correction that was specifically made by him. The following passage of evidence is relevant to Mr Jenkins’ involvement in this.
“A.  No, no, I didn’t do a calculation to come up with the 60. I was quoting from other people.
Mr Justice Fraser:  Someone just gave you the 60, did they?
  1. I thought I was quoting from other people.  I — Gareth even said to me that in my statement I had said “approximately 60”, so I was not — clearly I didn’t because the statement here doesn’t contain that word. I had rather hoped it had when this was first brought to my attention, but no, I certainly did not do any specific calculation to come up with the 60 that I put into my original statement.
Mr Green:  Did Gareth explain the change to you from 60 to 62?
  1. No.
  2. But how did he come to tell you what was in your original statement?  What was that conversation?
  3. I picked up the number — to be — my objective in this was to explain to the court the symptoms of the bug and how — the technical aspect of it.  I did not pay particular attention to getting the detail on how many branches were affected, correct.
  4. Okay.  So you have spoken to Gareth since your statement?
  5. I don’t think I have spoken to him about this in particular.  I was — as I say, when Gareth had said I had originally said “approximately 60” I was thinking that was quite neat, but that’s not the case.
  6. Well, you said “Gareth even said to me that in my statement I had said ‘approximately 60′”, so he must have said that to you after your statement had been filed?
  7. It was a comment in a document that we were exchanging.
  8. But you hadn’t spoken to him about remote access since your first statement?
  9. No.
  10. Why have you stayed off that topic with him?
  11. Oh, sorry, this was just a comment.  We have been exchanging documents, we have been commenting on documents, so it was not a particular conversation.  It is merely a case of Gareth had commented on this when it was pushed back to us that I had originally said 60 and actually the answer was different.”
  1. There is nothing wrong with Mr Godeseth correcting the number of affected branches from 60 to 62. There is also nothing wrong with him reproducing a number given to him by someone else, as long as it was properly identified that the information came from someone else, who ought to be identified (which it wasn’t in his statement, but was, in at least outline terms, in his cross-examination). The reason for reproducing these passages is simply to identify the extent to which Mr Jenkins was so closely involved in the litigation, a point relied upon by the claimants. There were a great many references throughout Mr Godeseth’s evidence, written and oral, about information he had obtained from Mr Jenkins.
  1. When the Post Office served their evidence of fact, the claimants had asked the Post Office why there was no statement from Jenkins, whether Mr Jenkins was available to give evidence, and also whether he was involved as one of a team of what the claimants referred to as the “shadow experts”. This description was challenged by the Post Office, and the question of shadow experts is addressed further at [556] below. No explanation was given for Mr Jenkins’ absence in response to these requests, or in evidence in the trial, although it was confirmed that Mr Jenkins was not one of the team of so-called “shadow experts”.
  1. There the matter might have rested. However, in the Post Office’s written closing submissions, an explanation of sorts was for the first time provided. This was in the context of two matters: firstly, by way of explanation of Mr Godeseth’s evidence, and potentially to downplay its impact; secondly, in relation to the claimants’ complaints about the second hand nature of some of the Post Office’s factual evidence because in large part this had emanated from Mr Jenkins. This explanation by the Post Office included the following passages in its written submissions:
“144. [The claimants] understandably complain that Mr Jenkins and the other source of Mr Godeseth’s information could have given some of this evidence first hand.  However:
144.1 Taking into account that Mr McLachlan’s evidence specifically addressed things said or done by Mr Jenkins in relation to the Misra trial, Post Office was concerned that the Horizon Issues trial could become an investigation of his role in this and other criminal cases.
144.2   Moreover, Post Office was conscious that if it only adduced first hand evidence in the trial, it would end up having to call more witnesses than could be accommodated within the trial timetable.
144.3   Furthermore, so far as Post Office was aware, the relevant parts of Godeseth 2 were most unlikely to be controversial. For example, the Misra trial was a matter of public record, the four bugs were covered by contemporaneous documentation and Post Office had no reason to doubt Fujitsu’s account of the documents it held.”
  1. In a footnote to paragraph 144.2 of the closing submissions, the Post Office added “…..As noted above, had its witnesses only given first hand evidence, Post Office estimates that some 34 additional witnesses would have been required.”
  1. The following are relevant in my judgment:
  1. Of primary importance is the principle that it is for each party to decide whom to call as a witness, and what evidence they may seek to obtain from any particular witness.
  1. Mr Jenkins is an important and central person so far as the operation, efficacy and robustness of Horizon is concerned, and also in respect of the number of incidents over the years that have led to PEAKs, KELs, problems and fixes. That is reinforced by the Post Office’s own closing submissions that stated, at paragraph 138, that there were two possible candidates for the witness giving the overview of Horizon, namely Mr Godeseth and Mr Jenkins. It also stated that taking into account Mr Jenkins’ involvement in cases before the CCRC (including the Misra case) the decision was taken to use Mr Godeseth. For that decision to have been taken, it is implicit that Mr Godeseth must know enough about the system to give the evidence that he did.
  1. The point in the footnote about a potential further 34 witnesses is not relevant to whether Mr Jenkins was, or was not, called by the Post Office. The Post Office did not at any stage apply to the court and explain that further time was required for the length of the Horizon Issues trial for the specific reason that relevant evidence of fact from the Post Office would require a particular minimum number of witnesses. However, given the primacy of point (1) above, it was entirely for the Post Office to decide whether to call Mr Jenkins or not, how many witnesses to call, whom those witnesses were to be and what the content of their evidence should include.
  1. The Post Office chose to proffer a reason for Mr Jenkins’ absence in closing submissions. They were not obliged to explain. However, the reason in paragraph 144.1 quoted above is not a valid reason for his absence. The claimants would have been entitled, in cross-examination, to put to Mr Jenkins any previous inconsistent statements he had made on the same subject, but obviously only if there were any. These could, potentially, have included previous statements he may have made in earlier proceedings, but in order to be allowed to do that, such statements would have had to be inconsistent with his evidence in the Horizon Issues trial. Putting a previously inconsistent statement on a particular fact is permitted as part of cross-examination if a witness’ evidence on that fact is in issue. However, the Horizon Issues trial would not have become “an investigation of his role in this and other criminal cases” – the Horizon trial was about the Horizon Issues. Also, this type of cross-examination would only have arisen if any statement(s) in the Horizon Issues trial was or were not consistent with those he had made in previous cases in which he had been involved.
  1. Regardless of the validity of the explanation given by the Post Office, Mr Jenkins was not called as a witness, and it merits repetition that it is entirely a matter for the Post Office which witnesses it called, and which it did not. No speculation is permitted as to what evidence he might have given in the Horizon Issues trial. It ought to be recorded however that no limit on the number of witnesses was imposed by the court on any party, and the Post Office could (had it wished) have called both Mr Godeseth and Mr Jenkins. Nobody forced the Post Office to choose one or the other.
  1. There is established authority that in certain circumstances the court can draw adverse inferences from the absence of a witness. The claimants do not invite me to draw any adverse inferences from the absence of Mr Jenkins, and I do not do so.
  1. The fact that the Post Office chose to advance certain evidence in the Horizon trial, that emanated from Mr Jenkins, by means of another witness saying “Mr Jenkins told me that…..” means that the claimants were deprived of the opportunity properly to test that evidence by asking Mr Jenkins about it. It also emerged in cross-examination, although not in his written report, that Dr Worden has also obtained certain information directly from Mr Jenkins. By dealing with the material in this way, and having deprived the claimants of the opportunity to cross-examine Mr Jenkins, the weight to be given to evidence emanating from Mr Jenkins is less than it would be otherwise.
  1. There are two consequences of the Post Office choosing to adduce such evidence in this way. The first is that Mr Jenkins did not have to undergo any cross-examination on such evidence; the second is that such evidence would not be given the same weight by the court as though Mr Jenkins had given it himself. The Post Office would have known this in advance, as this is wholly conventional. How these different factors were weighed by the Post Office and its legal advisers in deciding whether or not to call him, is solely a matter for the Post Office. The end result is that Mr Jenkins did not appear and was not cross-examined.
  1. However, I reject the suggestion that Mr Godeseth was insufficiently knowledgeable of the matters upon which he was cross-examined for his evidence to be of significant evidential weight. The Post Office’s Closing Submissions sought to dilute the effect of Mr Godeseth’s cross-examination by, at the same time, implicitly suggesting that Mr Jenkins (or someone else, but not Mr Godeseth) would have been a far better person to have answered those questions; yet explaining why Mr Jenkins had not been called. These submissions, though understandable from the Post Office’s point of view in forensic terms only, have little force. A clear choice was made by the Post Office not to call Mr Jenkins as a witness; that was their right. A clear choice was also made to call Mr Godeseth. The Post Office was are entitled to call such evidence as deemed necessary by both the Post Office and its advisers. They cannot, however, have matters both ways, and try to downplay Mr Godeseth’s evidence because he was called to deal with certain matters, and Mr Jenkins was not. The Post Office has to abide by the consequences of their choice of witnesses, in terms of the evidence now before the court to resolve the Horizon Issues trial. I have already explained my view of Mr Godeseth’s evidence in Part E above, and it need not be repeated. 
The judge was also critical of the Post Office’s position on disclosure. This led to some general points being made.
  1. The following points are of general application to both parties in this litigation. At some point a party who seeks to complain to the court about disclosure ought either to shelve its general disquiet on this subject, or make an application.
  1. It is important to identify, so that the parties in this group litigation are aware, the court’s approach to disclosure. This is given for the purposes of guidance, and cost-effective and efficient progress of the group litigation going forwards.
  1. Care must be taken when explanations or submissions are made to the court. If further time is needed in order for accuracy to be achieved, that time should be sought. Those giving instructions to counsel must be astute to ensure that they are giving correct information.
  1. All the substantive issues will be resolved on the evidence, the applicable law, and taking account of submissions. A party does not obtain a preliminary advantage or “head start” on the substantive issues because of any criticisms about disclosure.
  1. Criticisms about the other party’s disclosure should be proportionate. Depending upon the circumstances and the nature of the document, the fact that disclosure is given late might be relevant, but simply because continuing disclosure is given by one party does not mean that there is anything sinister lurking in the background.
  1. The court can always be asked to resolve disputes about documents. Mr Coyne sought a large number of different types of documents, but no applications were made by the claimants even though these were not provided. Criticisms of the Post Office’s disclosure by the claimants has to be seen in the light that the claimants did not consider it sufficiently important at the time to make any applications to the court. This is not to encourage applications. Sensible and well-advised parties who co-operate will usually deal with almost all disclosure issues consensually.
  1. The parties are expected to comply with their disclosure obligations. If a document comes to light that should have been disclosed but has not been, it should be provided promptly. If this is discovered actually during a trial, it must be disclosed very rapidly indeed. As happened with the document referred to at [618] above, a document concerning the Drop and Go bug was discovered actually during the Horizon Issues trial, then (as Mr Parsons put it in his explanatory witness statement) “for the next couple of months” kept by the Post Office’s solicitors while “research” was done. It was then disclosed just before resumption of the trial “in a batch”. This is not working to the time scale either required, or expected, by the court, and it is not the correct way to deal with disclosure during a trial. This is a laissez-faire approach to disclosure of an important document during the trial itself, and the document should have been disclosed very promptly.
  1. Both parties will be held to the same standards. The Post Office has, so far, and given the issues that have been tried, borne the bulk of the disclosure burden. The claimants are expected to observe their disclosure obligations in the same way, and will be expected to do so in the future when further issues and the claimants’ different cases are tried in 2020.
  1. Witness statements will be ordered from a party when the court requires an explanation. Nothing else should be read into the ordering of a witness statement, other than it means precisely that — an explanation is required.
  1. It is obvious that the Post Office has had to rely upon Fujitsu to a large degree. However, given it was Fujitsu who told the Post Office what the Known Error Log contained – see further [586] above – Fujitsu has, so far, shown itself not to be entirely reliable in this respect. Fujitsu are also responsible for the Post Office making a directly incorrect important statement in its EDQ about retention of KELs, which led to the disclosure of about 5,000 of these some months after the trial closed.
  1. Adoption of the Model C procedure does not mean that parties can keep adverse documents to themselves and not disclose them until a specific request is made. Such adverse documents should be disclosed promptly.
  1. Finally, disclosure is very expensive. The court will be astute to guard against it becoming either satellite litigation or a weapon in the interlocutory arsenal.
  1. I have exhorted the parties to co-operation many times before in this group litigation. I will continue to do so. Eventually, it is to be hoped that they will emerge into the broad sunlit uplands of the over-riding objective on disclosure matters.
The judgment also contains some important observations as to experts. In particular the Post Office’s expert had sent a supplemental report directly to the judge (without permission)
  1. The points that I draw from this episode are as follows:
  1. Experts should not serve their own material, particularly new material during a trial, and whether or not accompanied by detailed covering emails, directly upon the court themselves. Service should always be done by a party’s solicitors if solicitors are on the record.
  1. A party’s solicitors will know that all communications to the court must be copied to the other parties in the litigation.
  1. Experts should not notify the court directly of the intentions of their instructing solicitors and/or ultimate client in the litigation in which they are instructed. Such matters are privileged.
  1. It is difficult to be critical of Dr Worden in this respect, given he told the court that he was advised by the Post Office’s legal team to send his report directly to the court. Advice of that type should not be given to experts.
  1. Dr Worden must have considered that the documents upon which he relied were, at least, relevant. These were documents of a type sought by Mr Coyne in July 2018, whose relevance was disputed at that stage by the Post Office. Mr Coyne’s request ought to have led to these documents being provided to both the experts in the middle of last year, a reasonable period of time after Mr Coyne specifically asked.
The judge considered the evidence of the computer experts, Mr Coyne for the Claimant, Dr Worden for the Post Office.
  1. I prefer the expert evidence and approach of Mr Coyne to that of Dr Worden. This is for the following reasons.
  1. Dr Worden took a partisan view of the evidence of fact, preferring that of the Post Office’s witnesses (by which I mean in this instance predominantly Fujitsu) to that adduced by the claimants. This was most obvious in respect of his treatment of Mr Roll, but also occurred in respect of the claimants’ evidence of individual experiences of events caused by Horizon. No independent expert should do this. One example of this was the important issue of whether Fujitsu could inject transactions under Legacy Horizon without the SPM in question being aware of this. Dr Worden stated that he had “established” that these would be visible to SPMs. Mr Roll’s evidence of fact was directly to the contrary. Dr Worden had dealt with this by stating “So, in my opinion, Mr Roll could not have made these changes to branch accounts “without the Subpostmaster knowing”. In other words, in this expert’s opinion, the evidence of a witness of fact (and a very important one at that) was simply not correct in fact.
  1. However, in this case, even the Fujitsu witnesses eventually accepted (but prior to the trial, in their supplementary witness statements) that this had been possible, and that Mr Roll had been correct. Dr Worden’ supplementary report dealt with this by stating that there was a lack of understanding or clarity on this point. He stated that “it seems to me that I require further factual information before I can comment on this evidence” and also that “Mr Rolls new evidence does not cause me to alter the opinion expressed at paragraph 1119 of my first report, when commenting on Mr Roll’s first witness statement, that he could not alter branch accounts without the Subpostmaster knowing”. His first opinion in paragraph 1119 was wrong, and in my judgment obviously wrong, and this should have been unequivocally corrected both in his 2nd report and also in his cross-examination. The extract of this in [843] above makes it clear that he did not accept that.
  1. The sequence is therefore as follows. Mr Roll gave written evidence he had done something, and Fujitsu gave written evidence this was not possible. Dr Worden “established” that Mr Roll could not have done what he said he had done, and plainly preferred the Fujitsu evidence. He therefore adopted a position of which party’s evidence of fact was to be preferred. More factual evidence was then served and Fujitsu witnesses accepted this could be done, in contradiction to their earlier evidence. Dr Worden declined to “comment on this evidence” and remained of the view that Mr Roll could not have done that which he said he had done – in other words, his factual evidence was incorrect.
  1. No independent expert giving evidence to the court should do this. It is an obvious preferring of the evidence of fact of the party instructing him, added, in this case, to a refusal or failure to accept further evidence of fact to the contrary which subsequently emerged. This is even though the issue of remote access was accepted by the Fujitsu witnesses in supplementary statements.
  1. Mr Coyne did not do this. Indeed, he was fair and balanced in identifying where there were such differences, and he was also clear that he did not prefer one side’s evidence of fact to the other side. This is the correct approach for an expert to adopt.
  1. I find Dr Worden’s approach to the factual evidence I have identified concerning Mr Roll a particularly egregious failure to maintain the necessary standard of impartiality. Injection of transactions remotely into Legacy Horizon was an important factual point in this litigation, and indeed in the whole history of the ongoing lengthy dispute between the Post Office and the claimant SPMs. Further, in his expert declaration, Dr Worden went wider than the standard wording and specifically referred to an earlier decision in another case. He stated at paragraph 1194 the following:
“I understand that my duty in providing this report and giving evidence is to help the Court on matters within my expertise, and this duty overrides any obligation to the party by whom I am engaged or the person who has paid or is liable to pay me. I confirm that I have complied and will continue to comply with this duty. I have not assumed that any particular version of events is true and I have had regard to the case of Imperial Chemicals Ltd v Merit Merrell Technology Ltd [2017] EWHC 1763 (TCC) in producing my report”.
  1. That particular case (of which there are a number of judgments, on liability and quantum) concerned an expert and his preference for the evidence of fact of the party who had instructed him. I had stated in that judgment at [74] that “An expert’s role is not to decide issues of fact themselves, and choose what facts to believe and what not to believe”. Specific reference was made by Dr Worden to this judgment in his expert declaration. It might therefore be thought that the requirement upon him as an independent expert not to take a view on which factual evidence he preferred was, or should have been, at the forefront of his consideration. In any event, such an approach by the court to how experts should approach evidence of fact is not particularly ground-breaking. Independence requires an objective consideration by an expert of both sides of the factual evidence. It is the court’s role, not that of an expert, to decide which evidence of fact is accepted and which is not. Notwithstanding this, Dr Worden plainly accepted the initial factual evidence of Fujitsu and rejected the factual evidence of Mr Roll. Then when Mr Parker accepted Mr Roll’s account, Dr Worden still would not do so. He was quite wrong to do this on both occasions.
  1. Further guidance on the approach of an expert, if guidance be needed, is also provided in [237] of a later judgment in the same ICI v Merit series, namely [2018] EWHC 1577 (TCC) in which I stated:
“1. Experts of like discipline should have access to the same material. No party should provide its own independent expert with material which is not made available to his or her opposite number.
  1. Where there is an issue, or are issues, of fact which are relevant to the opinion of an independent expert on any particular matter upon which they will be giving their opinion, it is not the place of an independent expert to identify which version of the facts they prefer.”
  1. Dr Worden went so far as to state, in respect of his consideration of the variations in robustness of Horizon over time, that “in my opinion, as expressed in section 8, the Claimants’ shortfalls are not caused by bugs in Horizon, or any lack of robustness in Horizon.” The question of whether the claimants’ shortfalls was caused by bugs was not one of the Horizon Issues as I have explained above, but in any event, Dr Worden’s conclusions that the specific losses were not caused by bugs/lack of robustness was only reached by means of his statistical approach in section 8 of his first report. This was so heavily based on assumptions that were either not valid, or conceptually flawed, that his conclusions were not valid either. I would go further – the whole process he adopted so far as his statistical exercise was concerned was both invalid and of no evidential value.
  1. He also relied – in my judgment heavily – upon information from Mr Jenkins. Mr Jenkins was not even identified as one of his sources of information in section 1.3 of his first report, headed “Sources of information”. This means that Dr Worden was given access to information that was not made available to his opposite number, contrary to the point at (1) above in [878] above. Although there were some references throughout the text of the report to Mr Jenkins, Dr Worden did not routinely identify where he had relied upon Mr Jenkins. He also provided a great deal more information about this contact with Mr Jenkins in his oral evidence than he did in his written reports. In his cross-examination, he identified, when asked about a passage, that he had obtained that information from Mr Jenkins, which plainly took place before the first report was served as he accepted on his first day in the witness box it was “a year ago”. This was not clear in the report itself. One example of this was paragraph 654.2, where the report was dealing with the effect of the Receipts/Payments Mismatch bug, and Dr Worden stated “Because the operation involved was apparently not a double-entry operation on the BRDB, the countermeasure of checking the double-entry constraint DEA did not catch it”. This information came from Mr Jenkins, but until Dr Worden was asked this in cross-examination, no reader would be able to tell this. The involvement of Mr Jenkins in this explanation in his report was simply hidden. Nowhere was there a note or summary of all the information that had been given to Dr Worden by Mr Jenkins. In this litigation in particular, and given the involvement of and information provided by Mr Jenkins, who knew so much about the Horizon system, such a note or summary was, in my judgment, essential. This was particularly important given there was no witness statement from Mr Jenkins. Dr Worden had been provided with, and had used, information from Mr Jenkins in addition to the witness statements served by the parties.
  1. Dr Worden also introduced the concept of “lasting” and “transient” effect of bugs or defects on branch accounts. There was no such distinction in the Horizon Issues themselves. A further difficulty with this approach is that Dr Worden confirmed that even an impact on branch accounts that was corrected several months later by a TC would, so far as he was concerned, be of “transient” impact. A different way of stating the same concept is that, so far as he was concerned, “transient” could be of quite long effect. Given TCs are corrections generated outwith the Horizon system and are effectively corrective actions issued by the Post Office itself, this moved his consideration away from the generic Horizon Issues into the realm of the efficacy of the Post Office business systems as a whole, not only including Horizon but their human processes too. That is not what the Horizon Issues were concerned with, and he frankly admitted in his cross-examination that had he not done this, his opinion evidence would have been rather different. Mr Coyne did not use lasting and transient effect, and correctly addressed the actual Horizon Issues themselves, as drafted and agreed by the parties and as approved by the court.
  1. Dr Worden also adopted this different approach to impact upon branch accounts. Dr Worden only considered an effect or impact on branch accounts where a discrepancy loss (or gain) was not rectified by a correction such as a Transaction Correction, as set out in the entry in the 2nd Joint Statement about the experts’ different approaches. This ignored the word “potential” in the Horizon Issues themselves. In my judgment, that was a wholly unhelpful approach, and also had the effect of minimising or reducing the number of bugs that have an impact upon branch accounts. This can be demonstrated by considering the following hypothetical example.
  1. Consider a situation where there is a software bug, which in this instance I shall call H. The effects of H are such that they cause the branch accounts of a particular branch Post Office to suffer an unexplained loss of £999.99. This occurs, and the SPM of that branch contacts the helpline and goes through to SSC, who create a PEAK and identify this and after a few weeks of investigation, work out that this is an unexplained software bug which they have not come across before. A KEL is therefore also created identifying H. Future incidents of H occurring would (or should) lead to new PEAKs which will also (or should) link to the same KEL, and to the same bug. Fujitsu report to the Post Office about the existence of H, which they have now discovered, and understand is a software bug. The Post Office accept that the sum of £999.99 has arisen in the branch accounts as a result of H and issue a TC to the branch in that sum, to correct the unexplained loss in that sum in the branch accounts. If one were to use Dr Worden’s interpretation of impact upon branch accounts, by reason of the issue of the TC, H would not be a bug, error or defect with an impact upon branch accounts. Such an approach is, in my judgment, wholly artificial and incorrect. It also defies the proper meaning of the words.
  1. Mr Coyne also considered substantially more PEAKs and KELs than Dr Worden, by a factor of almost ten. Mr Coyne stated that he and his team had considered a broad total of about 7,500. Dr Worden had only considered a far smaller sample. Mr Coyne’s far more vigorous and thorough exercise relied far less on the process of extrapolation inherent in Dr Worden’s approach, who was inevitably basing his opinion on a far smaller sample than Mr Coyne. Given the breadth of the resources being deployed by the Post Office in conducting this case, I find it difficult to understand why Dr Worden restricted his consideration of PEAKs and KELs in this way. However, I consider that the conclusions of Mr Coyne, based on the far more substantial consideration of these important documents, are more reliable than those of Dr Worden.
  1. To be fair to Dr Worden, he entirely accepted that he and Mr Coyne had approached their evidence differently. He stated the following when explaining why he had not supported Mr Coyne’s information requests.
“A.  Well, basically I think it became evident, and it is evident now, that two experts took very different approaches, and my approach was top down, understand the architecture and work down through things like KEL.  So as far as I was concerned, I had plenty of information to go on.  And Mr Coyne’s information requests didn’t strike me as things that, yes, I have got to really see that because I was — had a different priority.  I was trying to do a top down understanding of the architecture and top down look at robustness, and so on and so forth. And so I had plenty of documents to look at, basically.  So I think it is the different approaches taken by the two experts that led to lack of overlap.”
  1. This continued:
“Q.  Sorry, not having supported the very many requests he had to make?
  1. Yes, I felt his interests were different from mine and I really had plenty to do.
  2. And you initially only looked at KELs, didn’t you, you didn’t actually look at PEAKs?
  3. No, I looked at KELs and I looked at PEAKs where they were relevant.  I felt that KELs were a more distilled form of information.  I felt they were sufficient in many ways, especially when you go and look at the PEAKs.
  4. You looked at one or two PEAKs referred to in the KELs you looked at?
  5. Yes.  Look at some of them where you feel the KEL doesn’t tell you enough.
  6. And Mr Coyne was looking at PEAKs and KELs?
  7. I think in the first report he was looking mainly at KELs, like me, and in his second report he turned on PEAKs.”
  1. The reason that PEAKs are of great assistance is that there is a great amount of further information contained in them than in the KELs, and they also give a far more complete picture of the number of different occurrences of a bug. Both types of documents are however useful. I do not know why Dr Worden should have seen Mr Coyne as having “different interests” to him.
  1. Dr Worden also entirely seemed either to misunderstand (or restrict his consideration of) Horizon Issue 1, which concerned bugs, errors and defects having the potential to cause apparent/alleged discrepancies or shortfalls in branch accounts or transactions, or undermine the reliability of Horizon accurately to process and to record transactions. When challenged about his approach to this, including the absence of the word “cause” and the use of the word “potential” in the issue itself, he stated the following:
“A.  What’s the distinction between having the potential and actually doing?  I mean, if it doesn’t actually do, then in some sense it didn’t have the potential.”
  1. This is not the correct, or conventional, use of the word “potential”. It also looks at the matter in reverse. In the context of the Horizon system, whether bugs, errors or defects in that system have, or had, the potential to impact branch accounts or transactions, should focus one’s attention upon the possible effect of those bugs, errors or defects. If, of course, a particular bug actually has had the effect of in fact impacting branch accounts, then by definition it must also have had the potential to do so. Actual effect is a sub-set of potential effect. It means impact upon branch accounts must have actually happened. However, potential effect does not require that impact to have actually occurred. The two terms are not synonymous. Dr Worden therefore moved away from the actual issues before the court, and approached a great deal of his evidence from the point of rather different issues, which he seemed to have narrowed down himself. I consider such narrowing of the issues to be unwarranted.
  1. In their opening submissions, the claimants summarised this different approach as follows:
“We respectfully will invite the court to adopt an approach more consistent with Mr Coyne’s approach which is to look at what actually happened with particular examples and trace them through to a reasoned and careful conclusion and then from the ground up, as it were, draw inferences upwards rather than from an overarching hypothesis downwards.”
  1. The “overarching hypothesis” was that of Dr Worden. Because he had taken such an overall view, and an overall view on the most recent performance and functionality of the Horizon System (which is now HNG-A as of February 2017, and is no longer HNG-X), the degree of assistance his evidence provided to the Horizon Issues across the whole life of the system, both Legacy Horizon and Horizon Online, was more limited than that of Mr Coyne.
  1. In this group litigation, when the first individual claims are being tried out, further analysis will be required of the actual branch accounts of individual claimants. That stage of the litigation will deal with actual branch losses, if any, that are said by the claimants to be due to the actual impact of the bugs, errors and defects which exist. It is at that stage that findings will be made about actual impact upon the branch accounts of the different claimants. Some of the bugs and defects are agreed by Dr Worden and Mr Coyne, and those that are not agreed are resolved by me in the Technical Appendix. It is against the background of those findings that individual claims will be resolved. The purpose of the Horizon Issues trial was to resolve the generic issues, as the parties were poles apart about even the existence of such bugs, errors and defects, and whether they had the potential to act upon branch accounts and transactions in the way alleged by the claimants. Dr Worden moved away from consideration of those specifically drafted and agreed Horizon Issues and answered rather different ones.
  1. I also consider that Dr Worden, in his approach to countermeasures, insufficiently differentiated between measures which were part of the Horizon system and those that were not. He also included items in his countermeasures that plainly ought not to have been included as such, for example those the result of human intervention or involvement, and manual inspection of data by SPMs.
  1. In my judgment, Mr Coyne emerged more or less unscathed from his four days of cross-examination by leading counsel for the Post Office. That is not to criticise the cross-examination itself, which was very thorough and careful. It is just that what the Post Office set out to demonstrate, including lack of impartiality on Mr Coyne’s part (if not positive bias), lack of reliability in his conclusions, and the other detailed criticisms of him, simply was not achieved. He was described as “evasive” in some of the Post Office’s closing submissions, a term which I find is somewhat wide of the mark in describing how he gave evidence in the case before me, and how he answered questions. He was also criticised in the same submissions as adopting “an approach [that] was simply to look for bugs without giving a proper sense of scale, context or even balance”.
  2. In the Post Office’s closing submissions, there is a section headed “Judicial criticisms of Mr Coyne’s approach” where reliance is placed on a judgment in Scotland, called CGI IT UK Ltd v Agilisys [2018] CSOH 112 by Lord Bannatyne. In that case, Mr Coyne had appeared as an expert and he was criticised by the judge for an unbalanced view, amongst other things. The judgment was handed down on 4 December 2018. The fact that he had been judicially criticised in that case was not specifically put to Mr Coyne. However, the substantive criticisms of him, that he gave unbalanced and selective evidence, and the other criticisms, were put to him, and he did not accept them. The point that he had been previously criticised in a judgment ought specifically to have been put by reference to that case, so that he could answer this point. However, in any event I have read (as invited in the Post Office’s submissions) the entire Scottish judgment, in which the evidence of Dr Hunt, Mr Coyne’s opposite number, was preferred to his evidence. I have done this with particular care, and I have also considered all the criticisms made of him in that judgment, as well as the ones put to him in his cross-examination before me. The Scottish judgment provides a full explanation of the shortcomings of his approach in that case. I have also taken this prior judicial criticism into account in weighing up his expert evidence in this trial.
  3. The Post Office, amongst other things stated that “it is submitted that the examples set out above [ie in the Lord Bannatyne judgment] show the same tendency to reverse and switch in response to difficult points.” In other words, it is submitted that Mr Coyne adopted the same approach in the Horizon Issues trial before me, as he had in the earlier case in 2018. I have considered the criticisms of Mr Coyne with particular care in the light of this previous judicial criticism, even though I do not have the benefit of Mr Coyne’s explanation to the specific points arising out of that case. I do not find his evidence in the Horizon Issues trial suffers from the same deficiencies as Lord Bannatyne found in that earlier case. In particular, one of those criticisms in CGI, that he had failed to consider material documents and matters, simply does not remotely apply here. He and his team had done an extraordinarily thorough job of examining many thousands of PEAKs and KELs, and many more than Dr Worden did. I do not find that Mr Coyne reversed his evidence, or switched, or that any of the other criticisms of him are made out. It may be that he has changed his approach as a result of his experience in that case or judgment, or there may be other reasons for it. However, I do not find the criticisms made of him to be made out in this case.
  4. In my judgment, given the Horizon Issues, which expressly include “bugs, errors or defects”, the approach of an IT expert to start by looking in detail at the large volume of the Fujitsu PEAKs and KELs for bugs is not only entirely sensible, it is verging on essential. I reject the criticism that Mr Coyne’s evidence was given without having any sense of scale, context or balance. I conclude that Mr Coyne was impartial in his evidence in the Horizon Issues trial, and was giving the court evidence that was entirely uninfluenced by the exigencies of litigation or the interests of the party who called him. I find that he was independent, and that his conclusions in this case on the Horizon Issues are reliable.
  1. There were some subjects upon which he became a little flustered in his cross-examination, for example on the final afternoon when he was taken to task for the entry in the 2nd Joint Experts’ Statement on an agreed passage where he and Dr Worden had agreed that “the number of distinct bugs, for which the experts have seen strong evidence of the bug causing a lasting discrepancy in branch accounts, is between 12 and 29”. That latter number had come from Mr Coyne and he wished to reduce the number, initially to 13 but then upon reflection to 21. Mr de Garr Robinson made a great deal of this, as one would expect of a skilled cross-examiner, but in reality it is a simple point, as I have explained above. It did show a change of position because the number of bugs changed as I have explained. However, it is easy to overestimate the degree to which making an error on figures in such circumstances does, or does not, represent a lack of reliability on the part of an expert who has performed a substantial body of work. It must be remembered that this was an agreed entry in an agreed Joint Statement that was 44 pages in length (the experts agreed four separate statements, running to 100 pages in total including appendix). I deal with the detailed analysis of each alleged bug in more detail in the Technical Appendix, but the fact that the number did not remain an immutable “29” in all circumstances is not, in my judgment, a point against Mr Coyne. His attempts to ensure the final number was correct was not as smooth as he might have liked, and it gave Mr de Garr Robinson an opportunity to deploy his forensic skill, but in reality it did not impact upon Mr Coyne’s reliability.
  1. Mr Coyne was widely attacked for a lack of partiality, and indeed, for positive bias in favour of the claimants. I do not find those complaints or criticisms to be well founded. They are not based on any real substantive instances that can be shown in any specific respect to represent Mr Coyne demonstrating any lack of impartiality. They are not made out. The points made are, in my judgment, insufficient grounds to dent his credibility as an independent expert whose evidence can safely be relied upon in resolving the Horizon Issues. He had not been previously instructed to undertake work for either party, and he had no previous involvement in the history of the wider dispute between the Post Office and SPMs concerning the Horizon system and its reliability. I found his evidence before me to be neutral and independent, and not influenced by the fact that he was instructed for the claimants.
  1. Dr Worden’s decision, very late in the day, to prepare his 3rd Report, appears – by reason of the dates – to have coincided with the dismissal of the recusal application. This matter was not explored at all in cross-examination and so it is not necessary to consider the timing of Dr Worden’s realisation that he could perform a new exercise. Given that his oral evidence to me was that he was advised to serve that 3rd Report directly upon the court, and effectively was left to draft the covering email to the court himself, I am reluctant to criticise him for this unusual approach unduly. This is therefore not something that I weigh in the scales to any appreciable degree in deciding whether his opinion evidence and conclusions are more, or less, reliable than those of Mr Coyne.
  1. I do not wish it to be considered that I am being universally critical of Dr Worden in all respects. He had done a substantial amount of detailed analysis in his two reports, and the overall knowledge that the court had, at the conclusion of the cross-examination of both experts, was very much greater than it had been prior to the commencement of the Horizon Issues trial. Dr Worden discovered some bugs himself, bugs that neither the Post Office and/or Fujitsu either knew about, or had admitted the existence of, prior to Dr Worden’s involvement in the litigation. He also took a sensible and considered view of some elements of the documentation, the importance or relevance of which had not been admitted by the Post Office earlier in the litigation, such as the KELs. Some of the matters that were agreed by Dr Worden with Mr Coyne in the 1st to 4th Experts’ Joint Statements saved a considerable amount of court time. His entries in particular in respect of the Bug Table, where he considered the detailed contents of a number of PEAKs and KELs, were useful as well.
  1. However, Dr Worden had become closely involved with the Post Office’s case in the litigation. In my judgment he took a partisan view of the evidence of fact of Mr Roll, which he should not have done, and he also seemed to be acutely aware of the Fujitsu position. For example, if there was a problem in Horizon that originated with Riposte, rather than part of the system written by Fujitsu, he was always enthusiastic to make clear this differentiation in Fujitsu’s favour. It was not relevant to the Horizon Issues whether bugs, errors and defects in Horizon were caused by Fujitsu or Riposte (provided by Escher, a separate company), or any other part of the system. These are all points that lead to the same conclusion, namely that in my judgment his expert evidence was not entirely independent of the Post Office’s and/or Fujitsu’s interests, and his conclusions were substantially less reliable than those of Mr Coyne. I do not know whether he had found himself subconsciously influenced by his discussion with Mr Jenkins or not, but regardless of the reason, his conclusions were not reliable and I reject them in favour of those of Mr Coyne.
  1. In all the major respects therefore, and taking account of all the points made both in cross-examination and submissions by both parties concerning their own, and the opposing side’s, IT expert, I prefer the evidence and conclusions of Mr Coyne to those of Dr Worden.
  1. Overall Conclusions
  1. My judgment concerning the two experts, which of their evidence I prefer and why, has been reached on free-standing grounds. Because of the different way that the experts went about their tasks, it was not possible to consider in detail and track in Dr Worden’s reports any analysis and possible explanation of single incidents, and attribute that either to a specific bug, error or defect, or something else which was none of these things. The approach Dr Worden had adopted for his written evidence did not permit that, as he was (in a sense) working from the other end (overall reliability) back towards the beginning (individual experiences), in contrast to the approach of Mr Coyne. Dr Worden himself described his approach as “top down”. Mr Coyne, on the other hand, using PEAKs and KELs in particular, identified a great many specific incidents that Fujitsu had recorded, which plainly demonstrated the existence of numerous bugs. Indeed, some of the terms used by Fujitsu made it crystal clear that these were known to be bugs. One notable example is the expression used by Anne Chambers – “this bug has been around for years” – in February 2006. Dr Worden did engage with the detail of PEAKs both in the joint expert meetings and also in his oral evidence, and the final result is that by the end of the trial, the summary at the beginning of Appendix 2 of the Post Office closing submissions, was forced to accept the existence of a great many bugs in Horizon. The extent and nature of their impact was not agreed, but the Post Office could no longer deny their existence.
  1. Those claimants who gave examples of specific incidents specified them as well as they could, and in my judgment truthfully and accurately. It was usually Ms Van Den Bogerd who, for the Pot Office, attempted to demonstrate that this was not what had occurred, often by means of assertions that if the SPMs had followed procedures properly, what they said happened, simply could not have happened. The Fujitsu witnesses gave some limited evidence of fact in relation to specific instances and some specific PEAKs and KELs. The Post Office’s counsel did their best to challenge the factual accounts that were given by the claimants. I have provided the relevant findings in respect of those matters above. I indicated at the Case Management Conference on 22 February 2018 that the Horizon Issues should be capable of resolution with limited, if any, evidence of fact. Both parties chose to submit factual witness statements and called factual evidence. The factual evidence submitted by both the parties was, in my judgment, limited as expected and required. With the exception of the matter to which I have already referred concerning the evidence of Mr McLachlan and Mr Henderson at the PTR, the extent of each party’s evidence of fact was not subject to challenge prior to commencement of the Horizon Issues trial.
  1. The factual evidence of specific instances was of assistance in coming to conclusions on the Horizon Issues. Indeed, I found some of the factual evidence to be of great assistance. That of Mr Roll and Mr Godeseth was extremely useful. The latter, one of the Post Office’s main witnesses and the Chief Architect of Horizon, was sufficiently damaging to the Post Office’s case on the Horizon Issues that they were, essentially, forced almost to disavow him, and the Post Office’s closing submissions were highly critical of the accuracy of his evidence. As a further example only, Mr Latif gave evidence that he had performed certain basic routine steps to transfer the sum of £2,000 between terminals, and (in accounting terms) that sum had – to use his word – “disappeared” from the Horizon system. The Post Office evidence challenging this was from Mrs Van Den Bogerd, and essentially amounted to an assertion that if certain steps had been followed by him, this should not, or could not, have happened. That would be all well and good in an ideal theoretical world that did not pay any attention to reality, but it entirely ignores Mr Latif’s primary evidence of fact. I accept that primary evidence from the claimants’ witnesses in this trial as I have explained in Part D. Mr Latif had been a trainer trusted by the Post Office to train other SPMs, as explained at [98] above. Other references in the documents show both Romec engineers, and even Post Office auditors, being recorded in PEAKs as witnessing events supporting the type of occurrences that underpin the claimants’ case. These were ignored by those at Fujitsu tasked with completing these PEAKs, and conclusions are shown in those PEAKs being drawn by Fujitsu that flew in the face of what had occurred. Mr Latif’s experience is extraordinarily similar to the Dalmellington bug, which is numbered 4 in the Bug Table. Mr Latif did not operate core and outreach branches, therefore his experience is slightly different to what happened at Dalmellington. However, if one is to take an objective and sensible view of the evidence of a previously trusted SPM, whom the Post Office itself has used to train other SPMs for some years, who stated that he did something correctly and X occurred, then meeting that with a bare assertion that X simply cannot have happened is not particularly sensible, nor is it persuasive.
  1. The approach by the Post Office to the evidence of someone such as Mr Latif demonstrates 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. 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).
  1. 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.
  1. When real world examples such as Mr Latif’s are put together with the expert evidence that I have accepted – or even with Dr Worden’s lower figure for accepted bugs of 11 different ones – it can be seen that this institutional obstinacy by the Post Office amounts to little more than repeated assertions that the Horizon system (both Legacy and Online) cannot be to blame for the claimants’ experiences, coupled with (for some) challenges to the claimants’ witnesses because the Post Office simply cannot accept their factual accounts. The findings that I have made, on the evidence in the Horizon Issues trial, show that the reality is rather different, and the existence of the bugs, errors and defects that I have found to exist do have the effect explained by Mr Coyne.
  1. The approach that I have adopted to the evidence can be considered as follows. Firstly, to consider the factual evidence, the relevant contemporaneous documents, and applying the burden and standard of proof, reach evidential findings. I have considered the challenges to that evidence, and if the specific instances of factual witnesses explaining what they experienced could be explained (as the Post Office sought to do with some of the SPMs) by them simply not being reliable, remembering incorrectly, having been careless or even (for some) being criminal. I have also considered all of the Post Office’s factual evidence in this trial, the explanations of the Post Office’s witnesses, and reached my factual conclusions. I have considered the expert evidence on its merits, and then tested my conclusions against the evidence of fact that was adduced by both parties, and considered whether my judgment on the evidence of fact matched and supported, or contradicted, or in any way affected or influenced my conclusions on the expert evidence. In a sense this was to consider the factual evidence, and the expert evidence that I accepted and preferred, separately, and see if they both reached the same conclusion. Secondly, the evidence can also be approached in a different sequence. This is by firstly considering the specific factual evidence, and then considering the expert evidence, and only in the light of the conclusions on the factual evidence. Alternatively, one could simply decide the Horizon Issues on the expert evidence alone, although that would be far less preferable and would ignore entirely the important factual evidence of the Fujitsu witnesses, in particular Mr Godeseth. However, even if that third way were to be adopted, the same answers to the Horizon Issues would, in my judgment, be reached.
  1. Whichever way is adopted, it must be remembered that any claimant can only ever have personal experience of one small element of the Horizon system on a number of occasions. The overview and historical performance of Horizon, both Legacy Horizon and Horizon Online, has to come from Fujitsu witnesses and the two experts. Dr Worden and Mr Coyne had far more of an overview of the life of the system, as did Mr Godeseth and Mr Parker. Mr Roll had experience of it in its early years, but his evidence was what led to the correct picture on remote access finally emerging.
  1. I have done all of these exercises. Regardless of whichever approach is adopted, the same conclusions are reached. In this respect, all roads lead to Rome. In my judgment, the evidence of the factual witnesses accepted by me entirely supports and corroborates the conclusions reached by Mr Coyne. Indeed, I would go further than this, and state that Mr Godeseth’s evidence alone is enough to support and corroborate Mr Coyne’s conclusions. When that is put together with the evidence of Mr Roll, and the concessions that were obtained from the Fujitsu witnesses (in the circumstances of their performance as witnesses, to which I have already referred) it is clear to me that the correct conclusions to be drawn on the Horizon Issues are those drawn by Mr Coyne, save and to the extent that I have modified them in any specific respect.
  1. I consider that the evidence of the Fujitsu witnesses in particular, both former and current, has been of considerable assistance to me in resolving the Horizon Issues. Mr Roll, Mr Godeseth, and even in his own way Mr Parker (though not in the way that Mr Parker himself would have intended) have all provided clear evidence of the problems with the Horizon system, the bugs, errors and defects within both Legacy Horizon and Horizon Online in its HNG-X form, the way that these problems were (or were not) dealt with, and the way that Fujitsu had powers which, until shortly before the trial started, Fujitsu sought to keep from the court, and may not even have fully disclosed to the Post Office. Because the extent of these powers was kept secret in this way, the Post Office finds itself now having made misleading public statements previously. If one looks back to an earlier case management hearing and reconsiders how Fujitsu, through the Post Office, sought to portray the contents and lack of importance and relevance of PEAKs and KELs, then it can be seen that there has been a pattern of considerable defensiveness over the Horizon System. There has certainly been a lack of transparency, and a lack of accuracy in description.
  1. I have explained above at [172] how the Post Office sought to draw a particularly glowing reference in Fujitsu’s favour from the evidence of Mr Roll in their closing submissions. The Post Office stated that from his evidence “….a clear picture emerged of Fujitsu as an organisation which was thorough, professional and conscientious and which took considerable care to ensure that matters were properly investigated and dealt with.” I have already stated that this is not a conclusion that can be drawn from the evidence of Mr Roll. Nor is it a conclusion that, in my judgment, can sensibly be drawn from the totality of the evidence taken together, both factual and expert, in the Horizon Issues trial. As an example, on too many occasions are there PEAKs that conclude at one point that user error cannot be to blame, only for a misleading closure code to be used for such a PEAK. Fujitsu personnel routinely refer in such documents to the known existence of bugs, without this (so far as the documents deployed in the trial are concerned) being communicated to the SPM in question in these terms. In places there is even debate at Fujitsu shown in the documents about whether the Post Office and/or SPMs should be told.  I do not see how a thorough, professional and conscientious organisation can have produced for disclosure in this litigation so many thousands of KELs during 2019 itself, both during and even after the trial. I reject that description; it is an inaccurate description of Fujitsu and/or its investigative motivation.
  1. I consider, as explained in the Technical Appendix, that Legacy Horizon was not robust, and that although Horizon Online in its HNG-X form was better than Legacy Horizon (not least, I consider, because Riposte was no longer part of Horizon) its robustness was questionable, and did not justify the confidence placed in it by the Post Office in terms of its accuracy. HNG-A is a different matter, and the experts are agreed that it is far more robust than Horizon in earlier times. On the face of the relevant KEL, it is not possible to say whether the Drop and Go bug, number 28 in the Bug Table, which occurred in June 2017, was HNG-X or HNG-A. However, if the latter, it is one of only two such items in the Bug Table that relate to the existing version of the Horizon system.
  1. I turn therefore to the points identified by Males LJ in Simetra Global Assets Ltd and another v Ikon Finance Ltd and another [2019] EWCA Civ 1413 to which I have referred at [74] above. I have already dealt with the first point, succinctness (obviously lacking in a judgment of this length). The second point is a requirement to consider all the evidence. I have done this, both for and against each of the cases advanced by both the claimants and the Post Office. I have not recited every single disputed fact as to do so would lead to an even longer judgment, and substantially delay production of this judgment well into 2020, and which would be contrary to the overriding objective. The third point is to identify the issues, consider the evidence in respect of the issues, and give reasons. For this trial, the Horizon Issues were agreed by the parties and approved by the court; the review of the evidence has been longer than is ideal, but I have considered it all, whether recited in this judgment, or the Technical Appendix, or not. The fourth point is somewhat salutary, namely that fairness requires that a judge should deal with apparently compelling evidence, where it exists, which is contrary to the conclusion which he proposes to reach.
  1. In my judgment, there is no such evidence advanced by the Post Office. It is pointless to speculate on how such compelling evidence might have been presented, if there had been any. The evidence that has been advanced for the individual occurrences, for example by Mrs Van Den Bogerd, can be seen once tested in cross-examination to amount to unfounded assertion and, sometimes, an expressed desire, even in 2019, to go away and do more research. This is not apparently compelling evidence to the contrary to my conclusions. Additionally, the time for further research by the Post Office is long past. The Post Office’s approach to evidence, even despite their considerable resources which are being liberally deployed at considerable cost, amounts to attack and disparagement of the claimants individually and collectively, together with the wholly unsatisfactory evidence of Fujitsu personnel such as Mr Parker. The Post Office evidence also includes a very high level overview of Horizon by its expert which amounts to little  more than a claim that it has worked quite or very well, most of the time. This is effectively what Dr Worden’s section 8 exercise consists of. Counsel for the Post Office at one point put to Mr Coyne that there was more likelihood of an SPM being hit by lightning than of having a bug, error or defect in Horizon cause a branch account loss in their branch. Mr Coyne did not agree with that, and neither do I. Indeed, such a point wholly ignores the enormous number of PEAKs that show that branch accounts were potentially impacted on a great many occasions.
  1. Also relevant are the other points which Males LJ went on to consider, namely the importance of contemporaneous documents. He stated the following on this subject at [48] and [49] of Simetra:
“[48] In this regard I would say something about the importance of contemporary documents as a means of getting at the truth, not only of what was going on, but also as to the motivation and state of mind of those concerned. That applies to documents passing between the parties, but with even greater force to a party’s internal documents including emails and instant messaging. Those tend to be the documents where a witness’s guard is down and their true thoughts are plain to see. Indeed, it has become a commonplace of judgments in commercial cases where there is often extensive disclosure to emphasise the importance of the contemporary documents. Although this cannot be regarded as a rule of law, those documents are generally regarded as far more reliable than the oral evidence of witnesses, still less their demeanour while giving evidence…..
[49] It is therefore particularly important that, in a case where there are contemporary documents which appear on their face to provide cogent evidence contrary to the conclusion which the judge proposes to reach, he should explain why they are not to be taken at face value or are outweighed by other compelling considerations. It is, however, striking that the judgment in this case contains virtually no analysis of the contemporary documents many of which appear to shed considerable light on the nature and purpose of the critical confirmations and the way in which they were understood.”
(emphasis added)
I have already explained that the subject matter of the Simetra case is very different to this one, and I emphasise here that my analysis of the contemporaneous documents is in respect of the Horizon Issues in the context of this case, not the Simetra case which concerned very different allegations. Here, the categories of documents that are most illuminating in terms of specific incidents with Horizon over the years are the very numerous PEAKs and KELs. These emanate from, and are created within, Fujitsu. They are, in my judgment, a very good means of getting at the truth in this case. They show what was going on and the type of unexplained problems that numerous SPMs were experiencing in practice over the years, as they were reported to the SSC. They contain statements made when Fujitsu personnel’s “guard is down and their true thoughts are plain to see”. Some of them also record that Romec engineers, or the Post Office’s own auditors, have seen what has occurred and ruled out user error. Notwithstanding this, Fujitsu attribute user error to what has occurred.
  1. They also contain some very telling expressions, not in the context of a Fujitsu employee giving evidence as a Post Office witness in this trial, but at the time, with such unguarded comments as Anne Chambers in February 2006 stating that “this problem has been around for years and affects a number of sites most weeks” and “this appears to be a genuine loss” on another occasion (as examples only). These entries are at odds to the publicly stated position by Fujitsu both then and indeed later. In my judgment, the PEAKs and KELs deployed in the Horizon Issues trial, and there were very many, are consistent with my conclusions on the evidence and the answers that I have arrived at to the Horizon Issues. Obviously no account was taken in any of the evidence, and no account is taken by me in this judgment, of the 5,000 KELs that Fujitsu only provided and disclosed in September 2019, months after the trial had ended.
  2. The Post Office’s internal Horizon Online Induction Training slides and accompanying notes dated 7 December 2009 form a useful snapshot of how Legacy Horizon was viewed. The purpose of HNG-X was “to deliver a significant reduction in the total annual cost of ownership of Horizon, whilst ensuring the system remains fit for purpose in the 21st Century.” These materials make it clear that this programme had been identified in 2005 and was “to deliver a significant reduction in the total annual cost of ownership of Horizon”. Legacy Horizon was seen within the Post Office as being very expensive, although its overall cost is not relevant to the Horizon Issues. The notes to these materials state:
“However, we need to continue to manage firmly any over-expectations of the frontline that Horizon Online will deliver improved functionality – they may see this as a missed opportunity so will not cure all the issues and problems that users have with Horizon although where practical, and at no extra cost, we have smoothed away a number of “rough edges”.
(emphasis added)
There was no significant upgrade or improvement in functionality intended as part of HNG-X.
  1. Another type of document that is illuminating in terms of the Horizon Issues are internal Fujitsu briefing documents, and to a lesser extent also some internal Post Office emails, that show the same approach to, or view of, Horizon within those organisations as are drawn by my conclusions. One example relates to the so-called Ping fix. After this was brought in, the number and value of TCs fell dramatically so far as Camelot/the lottery was concerned. This appears at [427] to [428] of the judgment on the Common Issues, Judgment (No.3). In 2007 there had been the following value of TCs in respect of the lottery: approximately (to 1 decimal point, which represents £100 thousand) £22.8 million; in 2008 there were £12.5 million; in 2009 there were £12.0 million; in 2010 this became £11.3 million; and in 2011 £4.5 million. In 2012, the year the Ping fix was introduced, these fell below £1 million for that year.
  1. The Introduction to a Post Office document of 2011 entitled “Transaction Acknowledgements – End to End Incident Management and Data Flow” explains the following purpose to the Ping fix:
The PING Project was part of the Back Office Efficiency Programme within Post Office Ltd.
The objective of this project was to automate a process that converts Client transactional data files (e.g. Paystation), into a data feed to the branch, i.e. a Transaction Acknowledgement file.
The branch will then process the data electronically on Horizon Online and thus avoid non compliance issues and the resulting cost to the business to process queries as a result.
Please note – The term PING is an internal Post Office Ltd term and branches and helplines will know this new functionality as ‘Transaction Acknowledgements’.”
(emphasis added)
  1. The compliance issues were caused by the fact that the lottery terminals were on one computer system, namely that operated by Camelot, whereas Horizon was the system operated by the branch that was selling the Camelot products, and there was no electronic transfer of data in to Horizon in respect of Camelot sales. The “objective” in the Post Office document makes it clear that the Ping fix is a required improvement to the functionality, to overcome issues caused by having two different systems which meant that there was (prior to the Ping fix) no automated process to convert the client transactional data files into the data feed necessary for Horizon for the branch accounts. This has nothing to do with correcting excessive carelessness or fault on the part of SPMs. It is, in my judgment, about remedying a deficiency in the functionality of Horizon. That document also made it clear, because there are express entries to this effect, that outages might mean that the system would not deal with the matters sufficiently or accurately. A template message for SPMs is even included in the document for when this occurs, although that template message would not inform SPMs that outages would lead to inaccuracies. It is plain that outages would indeed lead to this, as this is mentioned in many places in the document, and acknowledged by its authors. This information was not however, based on the templates, to be given to SPMs.
  1. A theme contained within some of the internal documents is an extreme sensitivity (seeming to verge, on occasion, to institutional paranoia) concerning any information that may throw doubt on the reputation of Horizon, or expose it to further scrutiny. One entry in a document that makes it clear that the Post Office itself had already recognised this is contained in a document authored by Mrs Van Den Bogerd, entitled “Extracts from Lessons Learned Log” and dated 11 November 2015. One entry under “issues identified” was as follows in respect of the Post Office’s behaviour up to that date:
Failure to be open and honest when issues arise eg roll out of Horizon, HNGx migration issues/issues affecting few branches not seemingly publicised.”
(emphasis added)
  1. The Post Office’s guard may have been down when that document was written; it predates issue of the first claim form by about 6 months. I consider that it is the type of document that Males LJ had in mind when he spoke of a witness’ guard being down, when their true thoughts are plain to see. It plainly records Mrs Van Den Bogerd’s view of the Post Office’s approach to Horizon when it was written in November 2015.
  1. In July 2016, following the disclosure of the Dalmellington bug, the following emails went to and from very senior people in the Post Office. On 1 July 2016 the Chief Executive, Paula Vennells stated to Alisdair Cameron and Rob Houghton, in the context of an article that had appeared on the internet about problems with Horizon:
“Subject: The Dalmellington Error in Horizon / problemswithpol
Dear both,
This needs looking into please. horizon/?iframe=true&theme_preview=true
[This is a reference to an internet post about a conviction of an SPM]
Can I have a report that takes the points in order and explains them.
Tim McCormack is campaigning against PO and Horizon. I had another note from him this am which Tom will forward, so you are both in the loop.
We must take him seriously and professionally.
This particular blog is independent of Sparrow but clearly related in that it appears to present similar challenges that were raised in the course of the scheme.
I’m most concerned that we/our suppliers appear to be very lax at handling £24k. And want to know we’ve rectified all the issues raised, if they happened as Tim explains.
  1. Mr Houghton of the Post Office sent it on to someone else on the same day, copied to Mrs Van Den Bogerd. This stated:
“I need an urgent review and mini <taskforce> on this one. It probably needs to link up heavily with Angela’s work as FSC are mentioned extensively – Angela cfi. I don’t know how we respond to this but can we section a few inside people to get all over it and give me/Al/ Paula evidence and understanding.”
  1. However, the same recipients also received the following message from Mr Houghton later on the very same day:
“Can you stand down on this please? [A redacted section then follows]
Any specific actions and I will revert.
My apologies.”
  1. The email chain is heavily redacted and therefore the reasoning behind this volte face within the Post Office is not shown, nor was it explained by any Post Office witness.
  1. Thus the entirely understandable initial reaction of the Chief Executive of the Post Office, that a point by point investigation was required in respect of specific criticisms of Horizon in respect of one particular SPM who blamed Horizon for shortfalls and discrepancies, appears to have been very swiftly shut down and not pursued due to a decision at what must have been very high levels within the Post Office. I can think of no justifiable reason why the Post Office, institutionally, would not want to address the Chief Executive’s points and investigate as she initially intended, and find out for itself the true situation of what had occurred.
  1. Both the recipients of the Chief Executive’s email of 1 July 2016 above are specifically named in the Technology Strategy Update Decision Paper of 30 January 2017 in which the following is stated specifically. Mr Houghton is the Author of the paper, and Mr Al Cameron is “the Sponsor”. Part of that document records:
“This document forms an update to the IT Strategy approved in July 2016 by the PO Board. In July we outlined that IT was not fit for purpose, expensive and difficult to change.”
The same document also states that “We need to quickly rationalise and resolve misaligned contracts enacted to support legacy IT, obsolescence, a lack of PO technical competence, particular focus on Fujitsu and Accenture” .
(emphasis added)
  1. This therefore means that the decision taken not to investigate further in July 2016 and to “stand down”, in itself a surprising decision for a reputable institution to take given all the circumstances, was taken at broadly the same time as a conclusion was reached that the IT “was not fit for purpose”. The reference to the “lack of PO technical competence” is a concern, given [75] of the Technical Appendix which makes it clear that currently the Post Office can introduce new clients into Horizon without requiring Fujitsu input. The level of competence may of course have changed since 2016. The IT Strategy, which is referred to in this Update Decision Paper, and outlined that “the IT was not fit for purpose” and which was approved in July 2016 by the Post Office Board is, in my judgment, entirely consistent with my conclusions on the evidence. It is not, however, consistent with the Post Office’s response to the claimants’ pre-action letter, or the Defence in the group litigation, or the evidence adduced by the Post Office in the Horizon Issues trial. The Post Office’s solicitors’ response to the pre-action letter is dated 28 July 2016, very lengthy, and states that “the investigations to date have consistently pointed towards human error or dishonest conduct in branches as the most likely cause of shortfalls.”
  1. Nor is it consistent with the way the Post Office explained, in its oral opening submissions, that the Post Office had been investigating incidents earlier in terms of bugs. So far as Dalmellington is concerned, the oral submissions were as follows:
“….even the documents that your Lordship saw this morning with the Dalmellington bug, your Lordship will see the rigour that’s applied. There’s concern that postmasters aren’t given advice that might be incorrect.  The rigour associated with that process and the determination of Fujitsu and the other people involved, the other stakeholders, to get to the bottom of what happened is quite striking in my submission.”
  1. Dalmellington was investigated in 2015, and the outcome of that investigation is available to this court. The outcome of that investigation is far from favourable to the Post Office’s position on bugs, errors and defects, and the robustness of Horizon. The oral submission that the Dalmellington bug was investigated rigorously (which it was) does not easily sit with the documents showing that one year later the Post Office specifically decided not to investigate other incidents at all, and to “stand down” those tasked with investigating it. This is notwithstanding that the Chief Executive’s initial (and in my judgment entirely proper, if not the only proper) reaction was that those allegations needed to be looked at “seriously and professionally”, that an investigation was needed, and that an urgent review and mini task force was required. Nor does it sit easily with the way that other bugs that were present in both Legacy Horizon and Horizon Online were investigated by Fujitsu.
  1. Further, a conclusion in terms that the IT is “not fit for purpose” is not something that would have been reached lightly in an IT strategy document, or approved lightly by the Post Office Board. The Post Office Board is a serious level within the organisation. The Board are not likely to be involved in, nor to have brought to their attention, matters that are anything other than serious, considered and fully researched. This conclusion in this internal contemporaneous document has not driven my conclusions on the evidence in the slightest. Rather, it is the other way around. I have reached my conclusions on the evidence independent of contemporaneous references such as this one, but then tested my evidential conclusions against these to see if there is a contradiction. However, there is none, and they are entirely consistent.
  1. There are only very isolated Post Office documents that are inconsistent with my conclusions. I shall deal with only one.  On 17 August 2015 the BBC Panorama programme broadcast a programme which contained allegations about Horizon. The contemporaneous response to that by the Post Office in its statement to SPMs started with the following passages, which I shall reproduce. The bold emphasis was present in the original:
“The Post Office wholly rejects extremely serious allegations repeated in BBC’s Panorama programme of 17 August 2015. The allegations are based on partial, selective and misleading information.
  • The Post Office does not prosecute people for making innocent mistakes and never has
  • There is no evidence that faults with the computer system caused money to go missing at these Post Office branches
  • There is evidence that user actions, including dishonest conduct, were responsible for missing money
  1. The first of those bullets point is for another day, and is not for this court in any event, for the reasons explained at [60] to [66] above. This judgment deals with the detailed background and technical evidence behind the second bullet point. The confidence expressed by the Post Office in 2015, in that second bullet point, in the computer system and its accuracy is not consistent with the evidence I have accepted, the expert evidence on the number of bugs in the Horizon system (both Legacy Horizon and HNG-X) and my findings. This Post Office document was however drafted for public consumption, and this must explain the inconsistency. To the extent that the second bullet point conflicts with my findings in this judgment, that public statement in 2015 by the Post Office is factually incorrect. This is not to make any findings on any individual claim, or on the cause of money said to be missing in the accounts of any particular branch Post Office or individual claimant SPM.
  2. In my judgment, a number of both the Post Office’s own internal documents, and Fujitsu ones too, namely those that were not drafted for public consumption, plainly support my conclusions on the evidence. Further, certain matters that have emerged in the Horizon Issues trial – such as discussions within Fujitsu itself as to whether the Post Office should be told certain detrimental information about the Horizon system, and the Post Office’s own decision at the highest level not to investigate certain matters as recently as 2016 – are of great concern. The Post Office has gone to great lengths over the years, and spent a great deal of time and a huge amount of public money, in defending the performance of Horizon. It is also the case that the Post Office must have been reliant on Fujitsu to a certain degree in terms of being provided with accurate information of a technical nature. That is not only obvious from the evidence, but has also been agreed by the experts in the 3rd Joint Statement. That accuracy from Fujitsu has not always been available, as demonstrated by this judgment.
  1. However, regardless of that – and this judgment does not deal with who, if anyone, at the Post Office knew precisely what about Horizon, and when, as these are not part of the Horizon Issues – in my judgment a number of the specific internal contemporaneous documents, rather than being contrary to my conclusions on the evidence, are entirely consistent with those conclusions. I do not know if the Post Office Board, who were told in July 2016 that its own IT was not fit for purpose, will be particularly surprised at the findings on the expert evidence in the Bug Table, and the number of admitted bugs. It does not much matter, for the purposes of resolving the Horizon Issues, whether they are surprised or not.
  1. The experts’ agreements in particular have been of great assistance, but everything has been considered. This judgment, together with the Technical Appendix, is of substantial length, and to recite everything that has been deployed by both sides, in terms of evidence, submission and reference to all contemporaneous documents, is neither necessary nor desirable.
  1. It must also be remembered that Horizon as it is today, or at least in the last couple of years since it became HNG-A, is a very different system to earlier times. Legacy Horizon ceased to be used in 2010. Modern Horizon Online as it is today is not the same as the online system that was introduced in 2010; it is different and more robust, on the agreed expert evidence, to the system as it was even when the litigation started with the issue of the first claim form on 11 April 2016. It became HNG-A in 2017, rather than HNG-X, and runs on a completely different Windows platform. The dates of the bugs in the Bug Table are (between them collectively) from 2000 to 2018, although there are far fewer in recent years. Having said that, some – such as Bug 8, Recovery Issues, and Bug 28, Drop and Go, have been experienced up to 2018 and 2017 respectively. The latter is a reference data bug and hence easily fixed. The Technical Appendix at [421] provides a summary of the different bugs from Legacy Horizon and Horizon Online. It can be seen that there were more in Legacy Horizon than HNG-X in any event, and far fewer in HNG-A. In any case, the cut-off date for claims to be issued in the group litigation is 24 November 2017, as extended by paragraph 15 of the 1st Case Management Order sealed on 27 October 2017.
  1. The Post Office has been very concerned as to the outcome of this litigation on its wider business. It described the group litigation as long ago as its Opening Submissions in November 2018 for the Common Issues trial as representing “an existential threat” to that business. I do not consider that these answers to the Horizon Issues represent a significant threat to the Post Office’s entire business. Findings in this judgment as to the performance and robustness of Legacy Horizon from 2000 to 2010, and then of Horizon Online (in both its forms, HNG-X and HNG-A) from 2010 to 2018 are not findings on the Horizon system as it exists at the date of this judgment. These findings cannot be routinely applied to the way that HNG-A operates as at December 2019. It is agreed by the experts that the Horizon System in its HNG-A form is now relatively robust. This judgment is a historical analysis of the Horizon System as it relates to the period in question in the group litigation, not a judgment upon Horizon HNG-A as it is today.
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