R v Lam (No 18)

The case of R v Lam (No 18) involved the appellant, Lam, who was charged with a serious criminal offence. The nature of the dispute centred around the admissibility and weight of evidence regarding lies Lam had told, which were argued by the prosecution to evidence a consciousness of guilt. The case was heard in the Supreme Court of Victoria.

The primary legal issue the court had to decide was whether the lies Lam told, which were demonstrably false, could be used as evidence of his consciousness of guilt. The court had to consider whether such lies, if established, could be considered a compelling and prominent hypothesis, or if there were other competing hypotheses that could explain the lies. Additionally, the court needed to determine whether the lie or the facts establishing the lie were an indispensable link in the chain of reasoning required for inferring consciousness of guilt, particularly in light of the centrality of these facts to Lam’s defence.

In its reasoning, the court held that for an inference of consciousness of guilt to be drawn from a lie, the lie must be demonstrably false and there must be a compelling and prominent hypothesis that the lie evidences guilt. The court also noted that if the lie or the facts establishing the lie were central to the accused’s defence, this could result in circular reasoning or a "bootstraps" argument. The court found that the standard of proof for implied admissions in such circumstances must be carefully considered, especially in a joint trial where multiple accused persons may have lied. Ultimately, the court concluded that the lies in question did not sufficiently establish a consciousness of guilt as there were plausible alternative explanations for the lies.

The court ordered that the evidence of the lies be excluded from consideration in inferring consciousness of guilt, and directed the jury to disregard this evidence in their deliberations. The outcome of the case highlighted the importance of ensuring that any inference drawn from lies told by an accused person does not rely on circular or speculative reasoning, and must withstand scrutiny against other plausible hypotheses.