Pennsylvania law, as does federal, permits a person accused of a crime to “defend” in part by proving their “good” character, limited to the pertinent trait. If the crime is robbery or assault, the defense is that the accused is nonviolent; and if the crime charged is forgery or theft, that the person is honest. The method of proof is by reputation—the character witness details what they have heard about the accused, with the typical response being “everyone says” or “people say” that defendant X is [fill in the trait].

And reputation testimony, an allowable form of hearsay, may be challenged on cross-examination. The character witness may be shown to be biased, closely related to the accused; the character witness may be shown to know the accused in only a limited way [e.g., “you only know X from school and not from the playground … ”]; and the character witness may be asked whether they have heard that the defendant has a criminal conviction for an offense that would be contrary to the character trait being asserted. It has to be trait-related and not too old. This is not to prove “bad” character but to attack the claim of “good” character.