“Housen v. Nikolaisen, 2002 SCC 33 (CanLII), [2002] 2 S.C.R. 235 confirms that different standards of review apply depending on the nature of the issue. For a pure question of law, the standard of review is correctness. For findings of fact, the standard of review is a palpable and overriding error. Where the trial judge draws inferences from facts, the standard of review first is whether the trial judge made any palpable and overriding error in making the factual findings and then whether the trial judge made any palpable and overriding error in drawing inferences from those factual findings (the second part of the test is not simply whether the inferences could reasonably be drawn from the factual findings).
For a mixed question of law and fact, if it involves the trial judge’s interpretation of the evidence as a whole, the standard is palpable and overriding error. If it involves the trial judge’s interpretation of a legal standard or its application, the error may amount to an error in law and be subject to the standard of correctness.
An appeal court must intervene when there is a material error, a serious misapprehension of the evidence, or an error in law. An appeal court is not entitled to overturn a trial judge’s decision simply because it would have made a different decision or balanced the factors differently. (See Hickey v. Hickey, 1999 CanLII 691 (SCC), [1999] 2 S.C.R. 518 per L’Heureux-Dubé J.; Van de Perre v. Edwards, 2001 SCC 60 (CanLII), [2001] 2 S.C.R. 1014 at paras. 11 and 12 per Bastarache J.) Bastarache J. in Van de Perre, supra, went on to state (at para. 15):
… the approach to appellate review requires an indication of a material error. If there is an indication that the trial judge did not consider relevant factors or evidence, this might indicate that he did not properly weigh all of the factors. In such a case, an appellate court may review the evidence proffered at trial to determine if the trial judge ignored or misdirected himself with respect to relevant evidence. This being said, I repeat that omissions in the reasons will not necessarily mean that the appellate court has jurisdiction to review the evidence heard at trial. As stated in Van Mol (Guardian ad Litem of) v. Ashmore (1999), 1999 BCCA 6 (CanLII), 168 D.L.R. (4th) 637 (B.C.C.A.), leave to appeal refused [1999] S.C.C.A. No. 117, [2000] 1 S.C.R. vi, an omission is only a material error if it gives rise to the reasoned belief that the trial judge must have forgotten, ignored or misconceived the evidence in a way that affected his conclusion. Without this reasoned belief, the appellate court cannot reconsider the evidence.”
Children’s Aid Society v. REA, 2009 CanLII 55338 (ON SC) at 67-69