This is my understanding.ConfusedL1 wrote:When can you use extrinsic evidence to impeach a witness? Never?
The general rule is that you can use extrinsic evidence to impeach a witness for anything OTHER than: pure character evidence or a collateral matter. The two exceptions are FRE 405(b) (using prior acts to establish character where character is an essential element of the cause of action or defense) and FRE 404(a)(2)(C) (prosecution can use any evidence to establish victim's peacefulness in order to rebut defendant's evidence that victim was the first aggressor in a homicide case).
The general rule applies whether you're impeaching the witness' character for truth and veracity ("CTV") or just establishing character evidence in general. If what you're asking about impeaches a witness's CTV and does nothing else, you can't use extrinsic evidence, but you can ask about it. For example, you can ASK the witness "you once stole money from your boss, didn't you?" If the witness says no, and there's no other relevance to that supposed act other than to attack the witness' CTV, you have to move on. This is the case even where you have a videotape that would easily establish that the witness is lying and that they did in fact steal the money.
Same goes for impeaching by collateral evidence. Say the witness testifies that he was eating a hamburger when he witnessed the vehicular accident that is the subject of the trial. You have a tape recording of him at the scene of the accident telling another bystander "I was eating a fish sandwich and I just saw that car hit the other car." You want to impeach the witness using this prior inconsistent statement. You can ask—"you said today that when you witnessed the car crash you were eating a hamburger, but isn't it true you told another witness the day the crash happened that you were eating a fish sandwich?," but once again you have to take the answer.
Impeachment that goes to bias or perception is never collateral, and only in rare instances will be categorized as going to the witness' CTV. Impeachment by prior inconsistent statement may or may not be considered impeachment on a collateral issue. So basically, if it's on something that isn't collateral and isn't purely related to the witness' CTV, you can use extrinsic evidence.
The whole idea of "collateral" is just an offshoot of FRE 403, the balancing test (which is invoked most often to weigh the probative value of evidence versus its prejudicial value, but also prohibits undue delay, waste of time, etc.). The circuit courts have basically said that when something is collateral (has no independent relevance other than contradicting the witness), it's a waste of time to have a little "mini trial" to actually prove the collateral evidence.