During a criminal jury trial, the Crown sought to introduce expert evidence from a police officer regarding a 'code of silence' within a Toronto neighbourhood, which allegedly discouraged witnesses from cooperating with police due to fear of retaliation.
The proposed evidence was tendered after key witnesses had testified and was intended to explain an eyewitness’s earlier reluctance to identify the shooter.
Applying the Mohan framework and the two‑stage admissibility analysis described in Abbey, the court found the proposed evidence met the threshold requirements of relevance and expert qualification.
However, the court concluded the evidence was not necessary because the eyewitness had already testified about the alleged code of silence and the jury could assess credibility without expert assistance.
The court held the potential prejudice—particularly the risk of implying gang involvement without supporting evidence—outweighed the probative value.