When can a prosecutor not present extrinsic evidence to rebut a witness?

The scenario in which a prosecutor cannot present extrinsic evidence to rebut a witness is when the witness has already stated their answer. In legal terms, extrinsic evidence refers to information that comes from outside the witness’s direct testimony to challenge or contradict what they have said.

When a witness has already provided an answer, introducing extrinsic evidence to rebut that specific testimony is typically not allowed because the opposing party (in this case, the prosecutor) must first confront the witness with the contradiction during direct or cross-examination. The intent is to allow the witness the opportunity to clarify or explain their statements, promoting a fair trial process. Only if the witness were to deny a statement or if the issue was not covered in their direct testimony would the use of extrinsic evidence be appropriate.

The other options involve scenarios where the rules regarding extrinsic evidence would not apply in the same manner. For example, a lack of credibility or unavailability of a witness does not directly dictate the use of extrinsic evidence to counter their testimony as dictated by evidentiary rules. The presence or absence of prior knowledge by the prosecutor similarly does not affect the admissibility of extrinsic evidence related to what a witness has already stated in court.