The Vancouver man accused of murdering eight people by ploughing a vehicle into a crowded street celebration on Saturday night had been grappling for months with the impact of his brother's murder.

Former attorney general Wally Oppal says that even when an accused killer has documented mental health problems, they can still be convicted for their crimes. Kai-ji Adam Lo, accused of plowing his SUV into a crowd Saturday afternoon, killing 11 and injuring more than 30, had dozens of interactions with police related to his mental health issues.

Vancouver Lapu Lapu Day Festival attack killed 11 people and left over 30 injured. The victims include a teacher, a real estate agent, and a 5-year-old girl.