What is the current state of the law on aiding and abetting?

Dunlop and Sylvester v. The Queen, 1979 CanLII 20 (SCC), [1979] 2 SCR 881 (“Dunlop”), dealt with aiding and abetting. At page 891, the majority pointed out: Mere presence at the scene of a crime is not sufficient to ground culpability. Something more is needed: encouragement of the principal offender; an act which facilitates the commission of the offence, such as keeping watch on enticing the victim away, or an act which tends to prevent or hinder interference with accomplishment of the criminal act, such as preventing the intended victim from escaping or being ready to assist the prime culprit. …