Related Sector: Witness Familiarisation

How do judges evaluate lay evidence?

What process is undertaken to determine its veracity?

Every so often a case comes along where the judge’s opening is so thorough that the judgment provides an invaluable analysis of a crucial part of the litigation process. Muyepa v Ministry of Defence [2022] EWHC 2648 (KB), with Mr Justice Cotter’s considerations for assessing witness credibility, is such a case.


On 20 July 2018, the Claimant, a former soldier, commenced proceedings against the Ministry of Defence, seeking damages for personal injury arising out of an alleged Non Freezing Cold Injury (NFCI).

It was admitted by the Defendant that if the Claimant’s claim was found to be genuine then there was a breach of duty. But if the injury was deliberately engineered to make a fraudulent PI claim or if the Claimant had knowingly significantly exaggerated his NFCI symptoms to such an extent that he had been fundamentally dishonest, then the claim must be dismissed.

The case therefore turned on whether the Claimant had been honest about the existence, causation, and extent of the NFCI symptoms.

Due to the large number of factual witnesses (29), Mr Justice Cotter’s judgment contained a thorough report of his approach to evaluating lay witness evidence.

Challenged evidence

Mr Justice Cotter stated that a challenged testimony must 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.”

He then continued, that the court must consider any 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’.”

Finally, he stated that ''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 W.L.R. 948). However, often a sufficient number of pieces may be fitted together to allow the full picture to be seen.”

A lying witness

Mr Justice Cotter then moved on to reflect on a situation where a witness admits to lying or is proved to have lied, stating that “it does not axiomatically mean that little or no reliance can be placed on any aspect of his/her evidence.”

The motive and context of the lies must first be considered, and the effect of the lies on his or her credibility generally, as well as other evidence given by the witness. Reference was made to standard criminal directions: if a Defendant has lied, a jury is told to bear in mind that it does not necessarily mean that he or she is guilty. For example, an innocent Defendant may lie to bolster their defence. By analogy, therefore, the same can arise in a civil claim. “A witness may lie to bolster an otherwise valid claim or defence to a claim.”

An expert in this case, Dr Mumford, described a phenomenon in hospitals and GP surgeries as “deceiving to convince”. However, Mr Justice Cotter made a vital distinction as to the motive. A person “who is trying to convince a treating clinician that their medical condition is worse than it truly is in order to convince them 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.”

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.”

Cross-examination is the gold standard test

Where witnesses are accused of lying, Mr Justice Cotter reminded the court that cross-examination remains the gold standard test. “It is now well recognised that caution must be exercised before placing weight on how the evidence was given…The assessment of witness evidence is not a beauty parade and Judges should not treat it as such.”

He referred to Peter Jackson LJ in B-M [2021] EWCA Civ 1371 at pp.23-5:

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….”


On demeanour of a witness, Mr Justice Cotter said:

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. 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.”

Analysing veracity

Mr Justice Cotter summarised his process for analysing the veracity of a witness, as follows:

  1. Establish the relevant base of facts that cannot be in dispute; a set of foundations against which the reliability of the testimony can be assessed.” This is not necessarily witness testimony, but evidence established by scientific fact.
  2. Consider the evidence of all the witnesses in turn…taking into account all relevant matters such as the following (this being a non-exhaustive list):
    • 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? He referenced the central witnesses, the Claimant and his wife, who had an obvious motivation to lie, particularly when the sums claimed are so substantial.
    • Is there the potential for unconscious bias? Mr Justice Cotter referred specifically to the Claimant’s family and friends’ recollections of events that were not particularly memorable at the time (a wedding reception). He also mentioned Leggatt J’s (as he then was) comments in Gestmin v Credit Suisse [2013] EWHC 3560 (Com) about modern psychological thinking on frailty of memory: “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.”
    • Is the extent of the recollection (or lack of it) plausible? Mr Justice Cotter stated that he struggled with the plausibility of some of the witness evidence – particularly those who claimed to be able to “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”.
    • It is internally consistent (or has the witness changed his or her mind)? Mr Justice Cotter referred specifically to the “Claimant’s failure to be consistent about whether his symptoms significantly improved in summer or not”.
    • 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. In this case, the Claimant’s counsel referred to the number of witnesses who stated that the Claimant loved army life, appeared a changed man since he left the army, used a stick and appeared disabled and showed others what he said were swollen feet.
    • That “ordinarily it is harder when cross examined to lie in a consistent and plausible way than it is to tell the truth.” Mr Justice Cotter confirmed that he found this to be the case with the Claimant’s and his wife’s evidence.
  3. Consider how the evidence all fits together and whether a sufficiently clear picture emerges.

Justice Cotter found that the Claimant’s testimony was inconsistent on important issues and much of it could not be accepted as truth, when tested against the objective, factual evidence. For example, whilst he had presented himself as being very significantly disabled, the surveillance evidence established that he could walk without a stick, drive and shop by himself.

Although the solider called numerous lay witnesses, their evidence did not present an accurate picture.


This case demonstrates just how integral witness conduct and performance are to the outcome. Despite the 27 lay witnesses giving testimony in support of the Claimant (versus the Defendant’s two lay witnesses), the judge still sided with the Defendant.

As explored above, this was principally due to the quality of the evidence: the inconsistencies, irregularities, biases, and lack of plausibility of the Claimant’s lay witnesses particularly when under cross-examination, when compared with the evidence of the Defendant’s witnesses, which was largely consistent with the objective evidence.

It is not known, although it seems highly unlikely, whether the Claimant’s witnesses had any form of witness training.

If they had attended Bond Solon’s Witness Familiarisation training, they would have learnt the importance of giving consistent evidence, ensuring the plausibility of their evidence and, where proper, making concessions, especially under cross-examination.


Author: Meera Shah, Content Manager 

This article was first published on 24 November 2022

Please leave a comment

    Want more information? Please call us on...

    020 7549 2549

    If you require any help or would like to discuss how Bond Solon can assist you in your training needs, please call us on: +44 (0) 20 7549 2549