Bias evidence shows a witness's motive to favor one side, admissible without a specific rule authorizing it.

Impeachment is the process of attacking a witness's credibility through prior inconsistent statements, bias, contradiction, or character for untruthfulness.

Lay opinion testimony permits a non-expert to offer opinions rationally based on their own perception.

Prior conviction impeachment permits attacking credibility with certain criminal convictions.

A prior inconsistent statement impeaches a witness by showing they said something different on an earlier occasion.

Refreshing recollection uses a writing or object to restore a witness's memory so they can testify from recall.

Witness sequestration excludes witnesses from the courtroom so they cannot shape testimony to match others.