What is the standard of review of a trial court's ruling on a motion under section 995 of the Criminal Code seeking to establish the corpus delicti?

The trial court had a different view. Applying a rule that "only a slight showing" of evidence need be made to establish the corpus delicti, it found, [17 Cal.4th 301] on the basis of "the transcripts of the preliminary hearing and evidence admitted at such hearing," that "[a]mong other things, there is extensive evidence indicating various sexual acts were perpetrated against the victim. Defendant's statements, highly corroborated by other evidence in other areas, can then be used to strengthen the evidence on the issue of oral copulation once the threshold is met, which I find was met in this case." Citing People v. Robbins (1988) 45 Cal.3d 867, 248 Cal.Rptr. 172, 755 P.2d 355, the court denied the motion under section 995.

We explained the standard of appellate review of a trial court's ruling on a section 995 motion in People v. Laiwa (1983) 34 Cal.3d 711, 195 Cal.Rptr. 503, 669 P.2d 1278. "[I]n proceedings under section 995 it is the magistrate who is the finder of fact; the superior court has none of the foregoing powers, and sits merely as a reviewing court; it must draw every legitimate inference in favor of the information, and cannot substitute its judgment as to the credibility or weight of the evidence for that of the magistrate. [Citation.] On review by appeal ... the appellate court in effect disregards the ruling of the superior court and directly reviews the determination of the magistrate holding the defendant to answer." (Id. at p. 718, 195 Cal.Rptr. 503, 669 P.2d 1278.)