What is the test for a not guilty plea in a sexual assault case?

In support of his position, the appellant relies on Adgey v. The Queen, 1973 CanLII 37 (SCC), [1975] 2 S.C.R. 426, wherein Dickson J., for the majority, noted that events after the entry of a guilty plea but before the imposition of sentence, “may indicate the accused never intended to admit to a fact which is an essential ingredient of the offence… or he may have misapprehended the effect of the guilty plea or never intended to plead guilty at all, in any of which events the judge may, in his discretion, direct that a plea of not guilty be entered or permit the accused to withdraw his original plea and enter a new one” (at p. 430).