A classic ruling from the Supreme Court of Canada this morning in R. v. Taillefer; R. v. Duguay. A teen is murdered. The prosecution failed to disclose necessary information to the defence. One accused gets a new trial, the prosecution is stayed for the other.

As Spence J. observed in his reasons in Caccamo (dissenting on another ground, Laskin C.J. concurring), courts must not hesitate to interfere where conduct of the Crown suggests there was unfairness at trial, at p. 796:

In my view, it is the duty of the court to be vigilant to assure itself that the appellant has had a fair trial and if the regrettable conduct of the prosecution, using that term to cover both the police and Crown counsel, ever results in unfairness then the court should act with decisiveness to reverse such unfairness.

In my view, the failure of the Crown in this case to disclose either the statement or the existence of the potential witness created such prejudice against the appellant that it cannot be said with certainty that he received a fair trial.

So by failing to honour its role in the Canadian system as a quasi-judical officer ensuring the defence has all relevant information, we may not know what happened or be able to now prosecute an actor in the events. The accused said they had an alibi and that "they had been threatened and beaten during questioning". The undisclosed information was witness reports in Crown possession confirming that the accused's vehicle was not at the scene, contradicting the evidence shared by the Crown from other witnesses that it was.

Read the whole ruling.