In Muyepa v Ministry of Defence [2022] EWHC 2648 (KB) Mr Justice Cotter set out detailed considerations for assessing witness credibility.  Here we look at the description of the process of analysing the credibility of the witnesses.


“But what of the mendacious witness? When a witness admits to lying, or is proved to have lied, it does not axiomatically mean, that little or no reliance can be placed on any aspect of his/her evidence. First the motive and context of the untruthfulness must be considered. Then consideration given to the effect on credibility generally and especially upon other evidence given by the witness concerning matters in dispute.”


The judge was considering a claim for damages for personal injury arising from A Non Freezing Cold Injury. It was admitted that, if the claimant was genuine, there was a breach of duty.  The judge found that the claimant had suffered a minor injury but that the claim for damages had been exaggerated and the claimant had been fundamentally dishonest.


Given the number of the witnesses before the Court the judge thought it necessary to set out the approach taken to evaluation of witness evidence.

The approach to the lay witness evidence

  1. Given the polarised cases of the parties, what is at stake, the fact that at least one person took the oath and perjured themselves to advance or undermine a very large claim, the large number of people interested in the case and also the content of the closing submissions it is, unusually, necessary to briefly set out my approach to evaluation of the lay witness evidence and the determination of factual findings. I do so with some considerable hesitation as Judges up and down the land deal with factual issues on a daily basis and much of what I will set out are elements of very basic Judgecraft.    
  2. In Pomphrey v Secretary of State for Health & North Bristol NHS Trust [2019] EWHC [2019] Med LR Plus 25   I stated as follows in respect of the determination of disputes as to the facts [4];
“[31] I start with some very general and basic propositions. When evaluating the evidence of a witness whose testimony has been challenged it should be broken down into its component parts. If one element is incorrect it may, but does not necessarily, mean that the rest of the evidence is unreliable. There are a number of reasons why an incorrect element has crept in. Apart from the obvious loss of recollection due to the passage of time, there may be a process of conscious or subconscious reconstruction or exposure to the recollection of another which has corrupted or created the recollection of an event or part of an event.
[32] The court must also have regard to the fact that there can be bias, conscious or subconscious within the recollection process. When asked to recall an event that took place some time ago within the context of criticism, people often take an initial stance that they cannot have been at fault; all the more so if the act in question was in terms of their ordinary lives; unmemorable. There is a tendency to fall back on usual practice with the tell-tale statement being “I would have” rather than “I remember that I did”.
[33] The approach to the exercise of fact finding in a complex case (when faced with stark conflicts in witness evidence) as necessarily requiring all the pieces of the jigsaw to be fitted together is often both flawed and an exercise in the impossible. This is because individual pieces of the jigsaw may be wrong, distorted to a greater or lesser degree, or absent. Indeed, it is not possible to make findings if the state of the evidence or other matters mean that it is not proper to do so (see generally Rhesa Shipping Co SA v Edmunds (The Popi (M) [1985] 1 WLR 948 ). However, often a sufficient number of pieces may be fitted together to allow the full picture to be seen.”
  1. But what of the mendacious witness? When a witness admits to lying, or is proved to have lied, it does not axiomatically mean, that little or no reliance can be placed on any aspect of his/her evidence. First the motive and context of the untruthfulness must be considered. Then consideration given to the effect on credibility generally and especially upon other evidence given by the witness concerning matters in dispute.
  2. As for motive for lying the standard criminal directions to a jury require them to consider, if there have been deliberate lies, why a Defendant has lied? In answering this question, the jury is told to bear in mind that a Defendant who tells a lie is not necessarily guilty: sometimes a Defendant who is not guilty will tell a lie for some other reason. One reason may be to bolster a true defence. So it may be in a civil claim. A witness may lie to bolster an otherwise valid claim or defence to a claim. Alternatively, the lying may solely be to obtain a benefit to which they know they are not entitled or secure protection for themselves, or a person with whom they have a bond, in the knowledge that if the Court knew the true facts such protection would not be afforded.
  3. In hospitals and GP surgeries there is a phenomenon which was described by Dr Mumford, an expert in this case, as “deceiving to convince”.  This phrase was adopted by Ms Collignon in her closing submissions in respect of any lie which the Court may find the Claimant or his wife told.  However a person who is trying to convince a treating clinician that their medical condition is worse than it truly is in order to convince of the need for, or to speed up, treatment  has a very different motive to a person who is deceiving medico legal experts and others as to the existence or extent of symptoms within the context of a personal injury, clinical negligence or benefits claim, with the sole aim of securing a level of damages or benefits they are unlikely to achieve were they not to deceive.
  4. When referring to consideration of the context of the lying, I mean assessing when and how the untruthful evidence was given and also its relationship with other elements of the claim.  In the present case the Claimant’s wife, Mrs Muyepa, admitted that she and the Claimant had deceived the care experts as to where she was living at the time of their interviews to assess care needs. The motive for doing so was that if the care experts were aware of the fact that she had left her husband in December 2018 this undermined a claim that she was available to give him care and assistance around the clock (and also undermined  the assertion that he was so significantly disabled he needed such care).The context was the knowledge (and in my view there must have been such knowledge) that past and future care would be valued by the experts and would be reflected in the damages claim. The Claimant and Mrs Muyepa knew that the deception would artificially inflate the claim. This was deception for financial gain in respect of significant elements of the claim. Subsequently a schedule was compiled and served based on an understanding which they well knew was false. The effect is that I have to consider all aspects of the evidence of Mr and Mrs Muyepa bearing in mind that they are prepared to lie not just to underpin, but to significantly inflate, any true claim. Before any consideration of the Defendant’s case or challenge to the opinion of Ms Kerby, the financial impact on her evidence was considerable. The Claimant’s schedule figures for care dropped by £675,363 when she was informed of the true position (which had only been detected by the Defendant through analysis of third party records).
“No judge would consider it proper to reach a conclusion about a witness’s credibility based solely on the way that he or she gives evidence, at least in any normal circumstances. The ordinary process of reasoning will draw the judge to consider a number of other matters, such as the consistency of the account with known facts, with previous accounts given by the witness, with other evidence, and with the overall probabilities. However, in a case where the facts are not likely to be primarily found in contemporaneous documents the assessment of credibility can quite properly include the impression made upon the court by the witness, with due allowance being made for the pressures that may arise from the process of giving evidence….”
  1. Demeanour in court is not entirely irrelevant; it can on occasions be instructive. It is usually far easier to tell the truth than to lie. There may be pauses as a witness may try to think through implications and remain consistent. There may be a failure to answer a direct question by deliberately going off at a tangent; so appearing to answer; but not answering at all[6]. However, the way evidence is given or “demeanour” must not be given disproportionate weight. The difficulty some witnesses will have in giving evidence (for a range of reasons) must be taken into account.  The overriding objective sets out that it is the aim of the Court to ensure a witness can give their best evidence, but the process often cannot be an entirely level playing field.  Judges give due allowance for the fact that the court room is often an unfamiliar and frightening place for those who appear as parties or to give evidence, and that some witnesses will find the process more stressful and difficult than others particularly if they have a mental health issue such as depression. Allowances must also made for education and use of language. On the other hand some witnesses may be calm and assured, but calculated and accomplished liars. I took these matters into account when assessing all the witness evidence in this case.
  2. Each Judge will have his or her own approach to the factors referred to by Jackson LJ. I usually take as a first step in the analysis of the veracity of a witness, establishing the relevant base of facts that cannot be in dispute; a set of foundations against which the reliability of the testimony can be assessed [7]. Establishing such facts does not rely upon witness recall; rather on what is established by scientific fact and/or the seemingly ever increasing amount of data we produce such as documents, photographs, emails, text messages, video and other footage.
  3. The Defendant’s records (only provided after an order by the Court) established that Mr Lessey’s evidence as to the date of a meeting was incorrect. Social media clips and surveillance evidence established that what Mr Muyepa stated about his ability to walk without a stick was also incorrect. However, the mistake made by Mr Lessey was in my judgment a relatively minor one and did not substantially undermine his evidence (he corrected it in evidence in chief). The same cannot be said of the effect of what could be seen on the screen when taken against what the Claimant had claimed to experts, and within his witness statements, to be the limits of his mobility.  
  4. The next step I take is to consider the evidence of all of the witnesses in turn. Ms Collignon properly placed very great emphasis during her submissions upon the number of witnesses prepared to give evidence on behalf of the Claimant. It was the method used to seek to prove that the Claimant was essentially honest and Mr Lessey was a liar. However the assessment of evidence it is not purely a numbers game. It is necessary to carefully consider the evidence of each witness critically taking into account all relevant matters such as the following (this being a non-exhaustive list):
(a)     Motivation. What if anything has the witness to gain or lose through their evidence being accepted and is the witness trying to help the court independently of his or her personal interests/allegiance?  As for the central witnesses, Mr and Mrs Muyepa had an obvious motivation to lie; all the more so when the sums claimed are so large. However Ms Collignon struggled with what Mr Lessey’s motivation to come to court to lie may have been. He said that he came forward when he saw the case in the paper as he knew it was being advanced fraudulently and having been the victim of fraud himself in the past, he thought it “right” to say something. Ms Collignon suggested to him that he was motivated by jealousy to come to court and perjure himself. Mr Lessey dismissed the suggestion and it would be an extra ordinary step to take if that was the sole motivation.
(b)     Is there the potential for unconscious bias?  Leggatt J (as he then was) in Gestmin v Credit Suisse [2013] EWHC 3560 (Com) referred to modern psychological thinking on frailty of memory and stated:
“19. The process of civil litigation itself subjects the memories of witnesses to powerful biases. The nature of litigation is such that witnesses often have a stake in a particular version of events. This is obvious where the witness is a party or has a tie of loyalty…to a party to the proceedings. Other, more subtle influences include allegiances created by the process of preparing a witness statement and of coming to court to give evidence for one side in the dispute. A desire to assist, or at least not to prejudice, the party who has called the witness or that party’s lawyers, as well as a natural desire to give a good impression in a public forum, can be significant motivating forces.”
In my view unconscious bias has to be borne in mind in particular when considering the evidence of the Claimant’s family and friends, particularly about events which were not particularly memorable at the time (such as what the Claimant did or did not do as one of many guests at a large scale wedding reception).
(a)     Is the extent of the recollection (or lack of it) plausible?
I struggled with the plausibility of the evidence of some witnesses that they could recall (with certainty) whether or not another guest who was not the centre of attention danced at any stage during a large scale wedding reception.
(b)     It is internally consistent (or has the witness changed his or her mind)?
A significant example in this case was the Claimant’s failure to be consistent about whether his symptoms significantly improved in summer or not.
(c)     To what extent is the evidence of any witness consistent, with and/or corroborated by, other evidence (lay, expert, documentary etc).  This includes considering whether other witnesses broadly agree on matters (bearing in mind that more than one witness could be wrong but that evidence may provide cross/mutual support.  Ms Collignon referred to the number of witnesses who stated that:
(i)          The Claimant loved army life;
(ii)         the Claimant had appeared a changed man since he left the army;
(iii)      the Claimant used a stick and appeared disabled;
(iv)        the Claimant showed others what he said were swollen feet
(f)  Ordinarily it is harder when cross examined to lie in a consistent and plausible way than it is to tell the truth. I found that to be the case with the evidence of the Claimant, Mrs Muyepa and Mr Lessey.
  1. Having heard all the lay and expert witness evidence I then considered how it fitted together and whether a sufficiently clear picture emerged (even if all the available pieces of the jigsaw did not fit together to show a completed puzzle). A clear picture did emerge.
  2. Having set out general process of analysis I now turn to the detail of the evidence.