[19] This is in line with the appropriate approach to be taken by a trial judge in assessing the reliability of evidence given by witnesses in the course of trial proceedings. Among the salient principles that guide this undertaking are the following:
(1) In circumstances where events have taken place long ago, the orthodox and sensible approach for a trial judge to take in assessing the credibility and reliability of the evidence of a witness about those events is to place primary emphasis on the objective factual surrounding material and the inherent commercial probabilities, together with the documentation tendered in evidence: Effem Foods Pty Ltd v Lake Cumbeline Pty Ltd (1999) 161 ALR 599; [1999] HCA 15, Gleeson CJ, Gaudron, Kirby and Hayne JJ at [15]–[16].
(2) A proper understanding of the chronology of events is critical and contemporaneous documents generally furnish the most reliable source of evidence as to what occurred or, at the very least, provide a generally reliable reference point from which to assess the reliability of witness testimony: ET-China.com International Holdings Ltd v Cheung (2021) 388 ALR 128; [2021] NSWCA 24, Bell P (with whom Bathurst CJ and Leeming JA agreed) at [25].
(3) Judicial notice has been taken of scientific research which casts doubt on the ability of a trial judge to tell truth from falsehood accurately based on the appearance of witnesses such that trial judges should limit their reliance on the appearances of witnesses and develop their conclusions, as far as possible, on the basis of contemporary materials, objectively established facts and the apparent logic of events: Fox v Percy (2003) 214 CLR 118; [2003] HCA 22, Gleeson CJ, Gummow and Kirby JJ at [30]–[31].
(4) There are multiple problems with a trial judge making demeanour findings, ranging from systematic error or bias, memory malfunctions, the possibility that witnesses may be dishonest about only parts of their evidence, that a truthful witness may give accurate or inaccurate testimony and that a dishonest witness may appear to be truthful. A trial judge should keep in mind the guidance provided in Goodrich Aerospace Pty Ltd v Arsic (2006) 66 NSWLR 186; [2006] NSWCA 187, by Ipp JA (with whom Mason P and Tobias JA agreed) at [26]:
These problems and doubts about demeanour findings explain why trial judges are expected to weigh their impressions as to demeanour carefully against the probabilities and to examine whether the disputed evidence is consistent with the incontrovertible facts, facts that are not in dispute and other relevant evidence in the case. Of course, demeanour may trump the probabilities, but it should be apparent from the judge’s reasons that the probabilities and consistency with other relevant evidence have properly been taken into account.
(5) A trial judge should exercise restraint when forming a view about the credibility of a witness based on demeanour in giving evidence because it is a stressful and unfamiliar experience for most people, and particular care must be exercised in making demeanour findings where a witness is from a different cultural and ethnic background to that with which the trial judge is familiar: Goodrich, Ipp JA at [21], citing Sir Thomas Bingham in “The Judge as Juror: the Judicial Determination of Factual Issues” (1985) 38 Current Legal Problems 1 at 10–11. As was observed in Société d’Avances Commerciales (Société Anonyme Egyptienne) v Merchants’ Marine Insurance Co (The Palitana) (1924) 20 Ll L Rep 140 [1924] 11 WLUK 83, by Atkin LJ at 152:
… an ounce of intrinsic merit or demerit in the evidence, that is to say, the value of the comparison of evidence with known facts, is worth pounds of demeanour.
This passage was quoted with apparent approval by Gleeson CJ, Gummow and Kirby JJ in Fox v Percy, at [30].
(6) The assessment of the credibility of a witness is a larger concept than demeanour and the latter is not to be overemphasised: White Constructions Pty Ltd v PBS Holdings Pty Ltd [2020] NSWCA 277, Bell P (with whom White JA agreed generally at [154]–[156]) at [106], citing Goodrich at [16]–[27]. See also Admiral International Pty Ltd v Insurance Australia Ltd [2022] NSWCA 277, Bell CJ (with whom Ward P and Macfarlan JA agreed) at [102]–[103], citing White Constructions, at [106] and [138] and Goodrich, at [16]–[27].
(7) It is important to bear in mind that the ordinary human experience of a witness makes their memory of conversations fallible, as eloquently stated in the following oft-cited passage in Watson v Foxman (1995) 49 NSWLR 315, by McLelland CJ in Eq at 319 (recently approved in Touma v Highfields Australia Pty Ltd [2024] NSWCA 160, Basten AJA at [18] (with whom White and Adamson JJA agreed)):
… human memory of what was said in a conversation is fallible for a variety of reasons, and ordinarily the degree of fallibility increases with the passage of time, particularly where disputes or litigation intervene, and the processes of memory are overlaid, often subconsciously, by perceptions or self-interest as well as conscious consideration of what should have been said or could have been said. All too often what is actually remembered is little more than an impression from which plausible details are then, again often subconsciously, constructed. All this is a matter of ordinary human experience.
(8) Oral recollection of conversations still plays an important role as evidence in a case, as explained inET-China.com, by Bell P (with whom Bathurst CJ and Leeming JA agreed) at [27]–[29] in the following terms (emphasis in original):
[27] Whilst the quality and accuracy of oral recollection of actual conversations should be treated with care and caution given the fallibility of human memory (of which there has been a growing appreciation within the judiciary in recent decades), oral testimony may still be of value and importance, as was recognised in the nuanced observations of Leggatt J (as his Lordship then was) in Gestmin SGPS SA v Credit Suisse (UK) Ltd [2013] EWHC (Comm) 3560 at [22] (Gestmin):
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. (emphasis added)
[28] Documents and events have to be understood in their context, and evidence of context will often be furnished by witnesses in their oral evidence. Documents, moreover, will not always present a complete picture of events. Indeed it would be rare that they do. Nor do contemporaneous documents necessarily or invariably convey or record the background or context in which events took place. That background or context will be familiar to the actors at the time of those events but may not always emerge from documents.
[29] Context is critical for at least two reasons. Documents and events take their meaning from their context. The context in which events occurred may not necessarily be apparent to a court many years later when hearing a case. A clear understanding of context, both commercial and cultural, is also important where, as in the present case, some or all of the events under consideration occurred overseas and in settings that may differ from those usually dealt with in domestic litigation.
