The Courts have long recognised in cases of fraud the importance of testing the veracity of accounts “by reference to the objective facts proved independently of [witnesses’] testimony, in particular by reference to the documents in the case, and also to pay particular regard to their motives and to the overall probabilities”: Armagas Ltd v Mundogas SA (The Ocean Frost) 1985 1 Lloyd’s Rep 1 at 57 (Lord Goff). It has thus, and rightly become a commonplace in commercial litigation that contemporaneous documents “are generally regarded as far more reliable than the oral evidence of witnesses, still less their demeanour while giving evidence”: Simetra Global Assets ltd v Ikon Finance Ltd [2019] 4 WLR 112 at §§48-49.

I was naturally referred to the well-known observations of Leggatt J in Gestmin SGPS SA v Credit Suisse (UK) Ltd [2013] EWHC 3560 (Comm) (reported at [2020] 1 CLC 428) at [15]-[22] which have been cited in many cases and which I need not repeat. Leggatt J. concluded as follows:

‘22. In the light of these considerations, the best approach for a judge to adopt in the trial of a commercial case is, in my view, to place little if any reliance at all on witnesses’ recollections of what was said in meetings and conversations, and to base factual findings on inferences drawn from the documentary evidence and known or probable facts. This does not mean that oral testimony serves no useful purpose – though its utility is often disproportionate to its length. But its value lies largely, as I see it, in the opportunity which cross-examination affords to subject the documentary record to critical scrutiny and to gauge the personality, motivations and working practices of a witness, rather than in testimony of what the witness recalls of particular conversations and events. 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.’

In the circumstances of this case, it is important to point out that the Court must be satisfied that the purportedly contemporaneous documents are reliable. If any of the purportedly contemporaneous documents are alleged to be forged, these allegations add an extra layer of complexity to the assessment of the evidence.

I also found some recent observations of Rajah J. helpful from his Judgment in South Tees Development Corporation v PD Teesport Ltd [2024] EWHC 214 (Ch), a case where the numerous witnesses were recollecting/trying to recollect, against an incomplete documentary record, uses of various rights of way dating back to the 1970s and 1980s. In the context of setting out [15]-[20] of Gestmin, Rajah J observed:

‘23. …  Memory plays tricks on people. It is perfectly possible for an honest witness to have a firm memory of events which they believe to be true, but which in fact is not correct.

…

30.

Although Leggatt J’s words have been sometimes taken as an encouragement to place no reliance on witness recollection, particularly when there is an abundance of reliable contemporaneous documentation, the Court of Appeal has confirmed that the assessment of the credibility of a witness’ evidence should be a part of a single compendious exercise of finding the facts based on all of the available evidence; see Kogan v Martin [2019] EWCA Civ 1645 and Natwest Markets Plc, Mercuria Energy Europe Trading v Bilta (UK) Ltd (In Liquidation) [2021] EWCA Civ 680 at paragraphs 50 and 51.

31.

Each witness’s evidence has to be weighed in the context of the reliably established facts (including those which can safely be distilled from contemporaneous documentation bearing in mind that the documentation itself may be unreliable or incomplete), the motives and biases in play, the possible unreliability or corruption of human memory and the inherent probabilities. Where there is reliable contemporaneous documentation, it will be natural to place weight on that. Where documents add little to the analysis, other secure footholds in the evidence need, if possible, to be found to decide whether it is more likely than not that the witness’ memory is reliable or mistaken.’