Velez v. State
In Velez v. State, 762 P.2d 1297 (Alaska App. 1988) which involved a defendant accused of "date rape" (i.e., accused of inviting a woman out, then using threatening words and/or behavior to coerce her into having sex with him).
At trial, the State offered testimony from two other women that Velez had engaged in similarly coercive behavior when they dated him.
The Court held that this evidence should have been rejected because the probative value of the evidence implicitly rested on the inference that Velez had a propensity to sexually assault his dating partners:
Velez's activities with other women were marginally relevant to show how he conducted himself with each of his victims, ... but this is pure propensity evidence, absolutely forbidden by Evidence Rule 404(b). Thus, the state cannot offer evidence that Velez coerced other women to support an inference that he had a disposition to force his affections on unwilling women, and then ask the jury to infer from that disposition that he forced his affections on the victim named in the indictment. Despite its relevance, this evidence is absolutely precluded by Evidence Rule 404(b). (Velez, 762 P.2d at 1303-04.)