The credibility of witness evidence.
This e-shot takes a look at the case of Gestmin SGPS SA v Credit Suisse (UK) Ltd & Anor. It is important for all litigators to be familiar with the approach taken by Gestmin. In many cases now, trial judges are approaching witness evidence by directly considering the Gestmin case. In other cases, the principles are applied even if not directly expressed.
When considering witness credibility, it is helpful to review the commercial case of Gestmin SGPS SA v Credit Suisse (UK) Ltd & Anor, which came before Mr Justice Leggatt, who was tasked with evaluating the evidence of a number of witnesses concerning various events that took place over a number of years. In an interesting judgment, Mr Leggatt considered the psychology of recollection, psychological research and what we know about the fallibility of human memory.
Mr Leggatt referred to the appropriateness of basing factual findings on inferences drawn from the documentary evidence on probable facts and set out principles to assist in assessing witness evidence.
He also highlighted the inherent problems with memory recall, especially given the passage of time and external influences, such as documents, some of which the witness may not have seen at the time. The problem is that memories are easily corrupted and rewritten each time they are called upon. There are usually many drafts of a witness statement, and therefore, this is happening over and over. It not only occurs when preparing a statement but also when preparing for the hearing itself.
Mr Leggatt did not think that oral testimony serves no useful purpose at all, but thought its utility is often disproportionate to its length. This does not mean oral testimony should be disregarded entirely but, in Mr Leggatt’s view, its value is largely in the opportunity it presents to subject the documentary record to critical scrutiny and to gauge the personality, motivations and working practices of a witness.
To summarise, the principles that were set out and considered from the Gestmin case were the following –
- Human memory is fallible
- There are common misconceptions with memory
- The faulty model of memory as a mental record
- Memory is especially unreliable when it comes to recalling past beliefs
- The process of civil litigation itself subjects memory to biases
- The procedure of preparing for Trial has a considerable interference with memory
- The difference between reconstruction and recollection
- The approach of the Judge
Since then, the principles set out in Gestmin have been applied and considered in a number of cases, and Mr Leggatt’s reminder of the need to approach witness recollection with caution is, no doubt, borne in mind by Judges at all levels of our trial system.
The key point of this case is “Above all, it is important to avoid the fallacy of supposing that, because a witness has confidence in his or her recollection and is honest, evidence based on that recollection provides any reliable guide to the truth.”
How can PIC help?
In line with above, we would advise to obtain as much information as to what can be recalled as being said or agreed, and locate all contemporaneous documents which are either supportive of a case for an analysis of what those documents show, or what might be inferred from those documents. These steps should be taken at the earliest stage of a case in order to assess its strength going forward.
Nicola Smith, Costs Consultant
02.03.2023