Rule 11-608. A witness's character for truthfulness or untruthfulness.

A. Reputation or opinion evidence. A witness’s credibility may be attacked or supported by testimony about the witness’s reputation for having a character for truthfulness or untruthfulness, or by testimony in the form of an opinion about that character. But evidence of truthful character is admissible only after the witness’s character for untruthfulness has been attacked by opinion or reputation evidence or otherwise. B. Specific instances of conduct. Except for a criminal conviction under Rule 11- 609 NMRA, extrinsic evidence is not admissible to prove specific instances of a witness’s conduct in order to attack or support the witness’s character for truthfulness. But the court may, on cross-examination, allow them to be inquired into if they are probative of the character for truthfulness of (1) the witness; or (2) another witness whose character the witness being cross-examined has testified about. By testifying on another matter, a witness does not waive any privilege against self- incrimination for testimony that relates only to the witness’s character for truthfulness.