In what circumstances have courts reversed a judgment entered in a criminal case following a court trial?

In People v. Holmes (1960) 54 Cal.2d 442, 5 Cal.Rptr. 871, 353 P.2d 583, this court reversed the judgment entered in a criminal case following a court trial, because, although the defendant was advised expressly of his right to a trial by jury, he "did not express in words a waiver" of that right. (Id. at p. 443, 5 Cal.Rptr. 871, 353 P.2d 583.) This court held that such a waiver "must be so expressed and will not be implied from a defendant's conduct." (Id. at p. 444, 5 Cal.Rptr. 871, 353 P.2d 583.)