The Federal Rules of Evidence state that a defendant's character can be proved either by evidence of reputation or by evidence of specific instances of conduct. However, evidence of specific instances of conduct is permissible only in cases where the defendant's character is in issue "in the strict sense." Fed. R. Evid. 405 Advisory Committee Note. This means that evidence of instances of conduct can only be used when character is "a material fact that under the substantive law determines rights and liabilities of the parties." The evidence is not offered to prove that the defendant did or did not act in conformity with a character trait. Rather, the existence or nonexistence of the character trait determines whether the defendant committed the offense. McCormick on Evidence § 187, at 551 (3d ed. 1984).
Because the kindliness of the defendant would not determine whether or not the defendant actually committed the assault charged in this case, the specific instances of kindliness could not be introduced as evidence of the defendant's character. Instead, the defendant could enter the testimony of the witness regarding the defendant's reputation in the community.
This question concerns evidence that the defendant committed an act during the offense as part of a habit of committing such acts. Specifically, in order for the evidence of the past act of habit to be admissible, must the court find proof beyond a reasonable doubt that the defendant committed this past act? The answer is no. The court need only determine that a jury could reasonably conclude that the defendant committed the past act.
The broad principle concerning the admissibility of evidence is that evidence must be relevant to be admissible. Fed. R. Evid. §§ 401 and 402; Huddleston v. United States, 108 S. Ct. 1496, 1500 (1988). In Huddleston, the Supreme Court specifically rejected the argument that evidence of a prior act can only be admitted ...