During a jury trial for cocaine trafficking, the Crown invoked investigation privilege to prevent disclosure of the surveillance location from which a police officer observed the accused during an undercover drug transaction.
The court reviewed the principles governing investigative technique and observation post privilege, balancing the public interest in protecting police methods and cooperating third parties against the accused’s right to make full answer and defence.
The judge permitted extensive cross‑examination regarding the officer’s ability to observe but prohibited questions that would reveal the precise surveillance location or whether the officer was inside or outside a building.
The jury was instructed that the privilege limited defence cross‑examination and that this limitation could affect the weight given to the officer’s testimony.
The jury ultimately acquitted one accused and convicted the other.
