The Crown sought to qualify an oral maxillofacial surgeon to provide expert opinion evidence on the diagnosis, mechanism, causation, direction of force, and magnitude of force of the complainant's jaw fractures in an aggravated assault trial.
Following a voir dire, the court qualified the doctor to opine on the diagnosis and mechanism of the injuries based on his extensive clinical experience.
However, applying the Mohan and Abbey frameworks, the court held the doctor was not properly qualified to opine on causation, direction, or magnitude of force, as he lacked specialized training, research, or prior qualification in those specific forensic areas.