In charging juries, trial judges are obliged to review the substantial parts of the evidence and relate that evidence to the issues the jurors must decide.

Beyond summarizing the evidence, a trial judge is permitted to opine on the evidence adduced at trial subject to certain limits.
The overarching principle is fairness. Within this principle of fairness is the recognition that the jury must remain the arbiter of the facts and that any comments made by the trial judge cannot amount to a rebuttal of the defence address to the jury or unfairly denigrate or undermine the position of the defence.

In R. v. Walker, 2019 ONCA 806, the trial judge offended this rule by offering an opinion on a critical piece of evidence that was stronger than the position the Crown had been prepared to advance: the Crown had conceded that a gun was not clearly identifiable in security video footage, while the trial judge opined to the jury that a gun was identifiable in the video.  The Crown withdrew its concession and in closing took a position with respect to the gun that aligned with the judge’s. The Court of Appeal for Ontario held that the trial judge’s comment rendered the trial unfair, as it had profoundly impacted the course of argument on a critical piece of evidence.

Stuart O’Connell, O’Connell Law Group (All rights reserved to author).

See R. v. John, 2017 ONCA 622, 350 C.C.C. (3d) 397, at paras. 108-10 (per Watt J.A.).

R. v. Lawes (2006), 80 O.R. (3d) 192 (C.A.), at para. 23, leave to appeal refused, [2006] S.C.C.A. No. 175, (per Rouleau J.A.).