166 Justice McHugh addressed the matter again in Longman v The Queen [1989] HCA 60; (1989) 168 CLR 79. This was a criminal case, but his Honour's observations about the effects of delay apply with equal force to civil proceedings. His Honour said (at 107–108):
The fallibility of human recollection and the effect of imagination, emotion, prejudice and suggestion on the capacity to "remember" is well documented. The longer the period between an "event" and its recall, the greater the margin for error. Interference with a person's ability to "remember" may also arise from talking or reading about or experiencing other events of a similar nature or from the person's own thinking or recalling. …
Experience derived from forensic contests, experimental psychology and autobiography demonstrates only too clearly how utterly false the recollections of honest witnesses can be.
Circumstantial Evidence
167 The applicant referred to the authorities dealing with circumstantial evidence. He submitted that the respondents' case in relation to some of the allegations of war crimes is circumstantial in nature. The respondents did not dispute the statements contained in the authorities to which the applicant referred. They did make the point that there were eyewitnesses to all the alleged murders other than the alleged murder during the mission to Fasil. They submit that it is only in relation to that murder that it can be said that their case is wholly circumstantial.
168 In Bradshaw v McEwans Pty Ltd (1951) 217 ALR 1, Dixon, Williams, Webb, Fullagar and Kitto JJ said (at 5):
The difference between the criminal standard of proof in its application to circumstantial evidence and the civil is that in the former the facts must be such as to exclude reasonable hypotheses consistent with innocence while the latter you need only circumstances raising a more probable inference in favour of what is alleged. In questions of this sort where direct proof is not available it is enough in the circumstances appearing in the evidence give rise to a reasonable and definite inference: they must do more than give rise to conflicting inferences of equal degrees of probability so that the choice between them is mere matter of conjecture (see per Lord Robson, Richard Evans & Co Ltd v Astley [1911] AC 674 at 687). But if circumstances are proved in which it is reasonable to find a balance of probabilities in favour of the conclusion sought then though the conclusion may fall short of certainty it is not to be regarded as a mere conjecture or surmise: cf per Lord Loreburn, above, at 678.
169 In a circumstantial case, all of the circumstances that are established by the evidence are to be considered and weighed in deciding whether the circumstances raise a more probable inference in favour of what is alleged (Australian Broadcasting Corporation v Chau Chak Wing [2019] FCAFC 125; (2019) 271 FCR 632 at [134]). Spigelman CJ considered the difference between permissible inference and conjecture and the difficulties on occasion in detecting the difference
