During a criminal proceeding, the defence sought to qualify a forensic odontologist as an expert on the diagnosis, causation, and assessment of oral maxillofacial trauma.
The court applied the admissibility framework for expert evidence and concluded the proposed expert possessed sufficient expertise to testify about diagnosis of mandible injuries and the mechanism and pattern of jaw fractures.
However, the court found the expert lacked specialized education, research, and practical experience regarding causation, direction of force, or magnitude of force relating to jaw fractures.
Applying the gatekeeping function for expert evidence, the court also held that permitting opinions on causation would risk intruding on the ultimate issue for the jury and could improperly influence fact‑finding.
The expert was therefore limited to opinion evidence concerning diagnosis and injury patterns.