R. v. Singharath, 2023 SKCA 6, January 6, 2023, at paragraph 22:
In determining whether an accused had the requisite state of mind, a trial judge may infer that a sane and sober person intends the natural and probable consequences of their actions. This is known as the common sense inference. It is a permitted inference, not a presumption. In Walle, the Supreme Court described the inference as providing a tool or “marker” for triers of fact “against which to measure the rather amorphous concept of intent” (at para 63). In assessing the specific intent required for murder, triers of fact must consider “the whole of the evidence that could realistically bear on the accused’s mental state at the time of the alleged offence” (at para 65). That said, as the Court observed, a trier of fact may resort to the common sense inference in deciding whether intent had been proved where there is no evidence “that could realistically impact on whether the accused had the requisite mental state at the time of the offence, or if the pertinent evidence does not leave [the trier of fact] in a state of reasonable doubt about the accused’s intent” (at para 67). Put another way, a trier of fact may not apply the common sense inference if they have a reasonable doubt based on the whole of the evidence, and in assessing that issue as the Supreme Court cautioned, a trier of fact “must carefully consider the evidence that points away from it” (at para 63).