Character evidence is one of the most misunderstood types of evidence available. It is also evidence that can backfire on the party calling the witness. As a rule, all relevant evidence is admissible in New York criminal trials. Relevant evidence is defined as evidence “having any tendency to make the existence of any fact that is of consequence to the determination of the proceeding” more or less likely. However, the general rule that all relevant evidence is admissible is subject to many exceptions.
One type of evidence that may intuitively seem like it would be admissible in a criminal trial, but is generally excluded from evidence, is evidence of a defendant’s prior bad acts. This includes both charged and uncharged crimes. Under the New York evidentiary rules, prior bad acts are “not admissible to prove that the person acted in conformity therewith on a particular occasion or had a propensity to engage in a wrongful act or acts. Essentially, this means that the government cannot use evidence of past crimes or wrongs to prove that a defendant was more likely to have committed the charged crimes there may however be other reasons why such prior crimes are admissible. This is why, absent a few exceptions, a defendant’s criminal history is not admissible if the defendant does not testify at the trial.
Evidence of a defendant’s prior bad acts, however, can be admissible in some situations where the government is introducing the evidence for a permissible purpose; for example to establish motive, opportunity, intent, preparation, common scheme or plan, knowledge, identity, absence of mistake or accident. A recent case illustrates how New York courts handle this issue.