P.

Under Evidence Code section 1108, in the trial of sexual offense charges, evidence the defendant committed another sexual offense may be admissible to prove that the defendant has a propensity to engage in such conduct. This case raises two questions.

First, if the proffered conduct occurred before the defendant had reached the age of 14, must the prosecution establish that the defendant knew the conduct was wrongful and was thus capable of committing a crime, as required by Penal Code section 26, paragraph One (Penal Code section 26(One))? We conclude such proof is required because section 1108 only permits admission of evidence of another sexual offense that amounts to “a crime” under state or federal law.

Second, does the trial court or the jury ultimately decide if the proffered conduct amounted to a crime? The Court of Appeal held that the question is for the jury and imposed a sua sponte duty to instruct on Penal Code section 26(One)’s presumption of incapacity as it relates to evidence admitted under Evidence Code section 1108 (1108 evidence). We reject that conclusion.

In laying the foundation for admissibility, the prosecution must demonstrate that previously…