Can a defendant obtain relief without showing prejudice as a result of the erroneous denial of a jury trial?

As noted, defendant argues that a defendant will rarely be able to establish prejudice as a result of the erroneous denial of a jury trial. This assertion assumes we would find harmless error in a case involving contested factual questions, an issue we do not now decide. Moreover, defendants have other potential means of protecting their rights, such as the possibility of writ relief. (Cf. People v. Pompa-Ortiz (1980) 27 Cal.3d 519, 529, 165 Cal.Rptr. 851, 612 P.2d 941 [defendant can obtain relief without showing prejudice where error is challenged by writ petition rather than on appeal]; People v. Wilson (1963) 60 Cal.2d 139, 32 Cal.Rptr. 44, 383 P.2d 452 [same].)