Evidence

Collateral Matter

A collateral matter is one that would not reasonably call into question the accuracy of the witness's testimony if it is not true.

Non-collateral contradiction is when extrinsic evidence calls into question the truth of a statement, such as by bias.

If extrinsic evidence does not reasonably call into question the accuracy of a witness's testimony, it is collateral evidence and not admissible under FRE 403.

• Because the court does not want a bunch of mini-trials over little, barely-related matters which would just waste time.
• You can still ask the question of whether that is true or not though.
• This is similar to subsequent remedial measures.