R. v. Romano, 2021 ONCA 211, April, 8, 2021, at paragraphs 14 and 15:

The actus reus is established when the accused’s conduct, viewed objectively, meets the standard in s. 249(1)(a) of the Code of “driving in a manner dangerous to the public, having regard to all the circumstances, including the nature, condition and use of the place at which the motor vehicle was being operated and the amount of traffic that at the time was or might reasonably have been expected to be at that place”: Beatty, at paras. 43, 45; Roy at para. 28.

The offence also requires that the accused’s objectively dangerous driving be accompanied by the required mens rea. That will be present where the degree of care exercised by the accused was a “marked departure from the standard of care that a reasonable person would observe in the accused’s circumstances”: Beatty, at para. 43. “While the distinction between a mere departure from the standard of care, which would justify civil liability, and a marked departure justifying criminal punishment is a matter of degree, the lack of care must be serious enough to merit punishment”: Roy at para. 28 (emphasis in original). The risks created by the manner of driving, and their foreseeability, are an important part of the analysis. “(T)he trier of fact must be satisfied that a reasonable person in similar circumstances ought to have been aware of the risk and of the danger involved in the conduct manifested by the accused”: Beatty, at para. 43.