The Use of Uncharged Misconduct Evidence to Prove Knowledge

Abstract:     
In public and private affairs alike, it is frequently important, and sometimes essential, to determine whether a person knew a certain fact at a particular time. During the Watergate scandal, the key question was what President Nixon knew and when he came into possession of that knowledge. Knowledge was an important issue during the Congressional investigations in to the Iran-Contra scandal as well. As people attempt to assess blame for the collapse of giant energy company Enron, they are asking the same question. In civil actions for fraud or prosecutions for possession of stolen goods or sale of illegal narcotics, conviction requires proof of knowledge. From the mundane drug case to the huge corporate failure and to matters of the highest national interest, the question of knowledge looms large.

Because a person's state of mind cannot be perceived directly, knowledge must always be proven circumstantially. If the circumstances of the event at issue supply a basis for an inference of the mental state, proof of those circumstances is rarely objectionable. But when proof of a particular mental state on one occasion is supplied by evidence of the same mental state on another occasion, and when that other occasion involved conduct that reflects adversely on the actor's character, the court must consider whether admission of the evidence would violate the rule forbidding guilt by character. Whether the evidence will be admissible depends in the first instance on whether it is relevant on a sufficiently compelling non-character basis. That determination, in turn, implicates a long-standing rule of evidence law that permits evidence of other misconduct to be used as long as its relevance does not depend on a forbidden character inference.

In some situations the probative value of uncharged misconduct evidence on the issue of the actor's knowledge is relatively great, while the risk of unfair prejudice from the fact-finder's misuse of uncharged misconduct evidence is comparatively small. In those situations, admission of the evidence, along with a limiting instruction, serves the goal of truth-determination that is so central to the trial. In other cases, the risk that the evidence will be used improperly is simply too great to tolerate, and the court should exclude the evidence. This paper examines the circumstances in which courts have grappled with the admissibility of other misconduct evidence to prove knowledge, identifies cases in which the evidence should be admitted as well as those in which it should be excluded, and critiques the courts' tendency to admit the evidence considerably more freely than is justified.

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