§ 791 [Prior Consistent Statements to Rehabilitate Witness]

When someone testifies in court, the other side often tries to attack their credibility by pointing out things they said before that don't match their current testimony. This rule deals with when a witness's own side can fight back by bringing up things the witness said earlier that do match their testimony.

Normally, you can't just bring up a witness's past statements to prove they're telling the truth now. That would be too easy to game. But this rule allows it in two specific situations. First, if the other side already brought up an inconsistent statement to attack the witness, you can bring up a consistent statement, but only if the witness made that consistent statement before they made the inconsistent one. Second, if the other side accuses the witness of making up their story recently or lying because of some bias or motive, you can bring up an earlier consistent statement, as long as the witness made it before that bias or motive existed.

The main point is timing. A prior consistent statement only helps rebuild credibility if it was made before the problem came up, whether that problem is a contradicting statement or a reason to lie. If the consistent statement came after the bias or motive started, it doesn't prove much, since the witness could have already been influenced by whatever is being claimed.