What is the test for admissible evidence of sexual abuse?

We emphasize that it is the exclusive province of the trial court to determine whether the probative value of evidence outweighs its possible prejudicial effect. (People v. Sassounian (1986) 182 Cal.App.3d 361, 402.) And, like the trial court's initial determination of relevance, the trial court's exercise of discretion on this issue will not be disturbed on appeal absent a clear showing of abuse. (Ibid.)

It is true that evidence of uncharged offenses can be so prejudicial that its admission requires extremely careful analysis and, since substantial prejudicial effect is inherent in such evidence, uncharged offenses are admissible only if they have substantial probative value. (People v. Ewoldt (1994) 7 Cal.4th 380, 404.) But this rule is primarily one for the trial court in the exercise of its discretion. Our task is simply to determine whether the trial court could have rationally concluded that the probative value of the evidence outweighed the prejudicial effect.