James

Evidence Code sections 1108 and 1109 dramatically revised the law of evidence in sex offense and domestic violence cases by making prior offenses admissible to prove the defendant’s propensity to commit a charged offense. Here we consider an issue currently dividing the Courts of Appeal. An early version of the standard jury instructions permitted the jury to infer from the defendant’s prior offenses, proven by a preponderance of the evidence, that the defendant had a disposition to commit similar offenses, and to draw a further inference from this disposition that the defendant “was likely to commit and did commit the crime of which he is accused.” Does this chain of inference violate the constitutional requirement that the prosecution prove each element of the charged offense beyond a reasonable doubt?

We hold the instructions violated due process by increasing the likelihood the jury would misuse evidence of prior offenses, opening the door to conviction based merely on propensity. Propensity evidence tends to be highly persuasive. By itself, however, it can never prove guilt. Suggesting that the jury can base its verdict directly on an inference from propensity…