During a criminal trial for trafficking in a controlled substance and possession of property obtained by crime, the Crown sought to qualify a police officer as an expert in street drug slang.
The defence challenged the admissibility of the proposed expert evidence on the basis of lack of independence and inadequate expertise linking slang terms to specific controlled substances.
Applying the Mohan framework and the Supreme Court’s guidance in White Burgess, the court found that although the officer possessed experience with drug slang, his substantial involvement in the investigation created a realistic concern about his ability to act as an independent and impartial expert.
The court concluded that the Crown failed to establish the independence requirement on a balance of probabilities.
The proposed expert evidence was therefore excluded.
