“An appeal is not an opportunity to reargue a motion or trial. The decision of the original motions judge or trier of fact remains unless the appellant can show an error of law or fact was committed.
When considering potential errors of law, the standard of review is one of the correctness. Where an error of law is found, the appellate court is free to replace the opinion of the trial judge with its own: Housen v. Nikolaisen, 2002 SCC 33, [2002] 2 S.C.R. 235, at para 8.
When considering potential errors of fact, the standard of review is that an appeal will not be granted unless it can be established that the trial judge made a palpable and overriding error. Absent such a finding, deference is given to the trier of fact who was able to observe witnesses and hear the evidence first hand: Housen, at para. 10.
A palpable and overriding error is where a finding of fact is clearly wrong, unreasonable or unsupported by the evidence and the error affected the result of the motion or trial. This applies whether there is direct proof of the fact in issue or indirect proof of facts from which the fact in issue has been inferred: H.L. v. Canada (Attorney General), 2005 SCC 25, [2005] 1 S.C.R. 401, at paras. 53-56.
Matters of mixed fact and law lie along a spectrum. If there is an extricable legal principle, then that legal question will be reviewed on a correctness basis. Otherwise, if there is no extricable legal error, the standard of palpable and overriding error applies: Housen, at para. 36.
Trial judges are entitled to considerable deference when their decisions are reviewed. This promotes finality in family law matters and recognizes the importance of the appreciation of facts by a trial judge. While an appeal court must intervene when there is a material error, a serious misapprehension of the evidence, or an error of law, it is not entitled to overturn a support order simply because it would have made a different decision or balanced the factors differently: Hickey v. Hickey, 1999 CanLII 691 (SCC), [1999] 2 S.C.R. 518, at paras. 10, 12. This principle is equally applicable to orders concerning child custody: Van de Perre v. Edwards, 2001 SCC 60, [2001] 2 S.C.R. 1014, at para. 12.”