Evidence: Review and Summary: Impeachment

Review: Methods of Impeachment M
Impeachment Method	Means of Proof	Foundation
Prior Inconsistent Statement	Cross-examination Extrinsic evidence (if not a collateral matter)	Witness must be given opportunity to explain or deny the inconsistent statement (Exception for hearsay declarants)
Bias, Interest or Motive to misrepresent	Cross-examination Extrinsic evidence	Witness must be asked on cross-examination about facts showing bias or interest before extrinsic evidence is allowed. If those facts are admitted on cross examination, admissibility of extrinsic evidence is within court’s discretion.
Sensory Deficiencies	Cross-examination Extrinsic Evidence	None required
Reputation or opinion	Calling other witnesses	None required
Criminal Convictions	Cross-examination Record of judgment	None required
Bad Acts	Cross-examination only	None required
Contradiction	Cross-examination	If the contradiction goes to an issue that is significant to the case, extrinsic evidence is allowed. If the contradiction goes to a collateral matter, proof is limited to intrinsic evidence.