“In preparing reasons in custody cases, a trial judge is expected to consider each of these factors in light of the evidence adduced at trial; however, this is not to say that he or she is obligated to discuss every piece of evidence in detail, or at all, when explaining his or her reasons for awarding custody to one person over another. This would indeed be an unreasonable requirement at the end of a 26-day trial. Because of this, trial judges might sometimes appear to stress one factor over another and, in fact, it may be said that this is inevitable in custody cases which are heavily dependant on the particular factual circumstances at issue. This situation does not open the door to a redetermination of the facts by the Court of Appeal.
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As I have stated, the Court of Appeal was incorrect to imply that Hickey, supra, and the narrow scope of appellate review it advocates are not applicable to custodial determinations where the best interests of the child come into play. Its reasoning cannot be accepted. First, finality is not merely a social interest; rather, it is particularly important for the parties and children involved in custodial disputes. A child should not be unsure of his or her home for four years, as in this case. Finality is a significant consideration in child custody cases, maybe more so than in support cases, and reinforces deference to the trial judge’s decision. Second, an appellate court may only intervene in the decision of a trial judge if he or she erred in law or made a material error in the appreciation of the facts. Custody and access decisions are inherently exercises in discretion. Case-by-case consideration of the unique circumstances of each child is the hallmark of the process. This discretion vested in the trial judge enables a balanced evaluation of the best interests of the child and permits courts to respond to the spectrum of factors which can both positively and negatively affect a child.
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As indicated in both Gordonand Hickey, 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 [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.”
Van de Perre v. Edwards, [2001] 2 SCR 1014, 2001 SCC 60 (CanLII) at 10, 13 & 15