What is the standard of review for a motion to overturn a finding of not guilty?

With respect to the standard of review the appellant relies on Stein v. Kathy K. (The), 1975 CanLII 146 (SCC), [1976] 2 S.C.R. 802, where the court found that the findings of fact made at trial are not to be reversed “unless it can be established that the learned trial judge made some palpable and overriding error which affected his assessment of the facts” yet found it is not the function of the reviewing court to substitute its assessment of the balance of probability for the findings of the judge who presided at trial. In Stein, the court was a court of record.