Impeachment
Attacking the witness, not the fact. Any party may impeach any witness—including their own (FRE 607). Five methods, each with its own extrinsic-evidence rule.
The five methods at a glance
| Method | What it shows | Extrinsic evidence? |
|---|---|---|
| Prior inconsistent statement | The witness told a different story before | Yes—if given a chance to explain or deny (FRE 613(b)); not on collateral matters |
| Bias or interest | A reason to shade testimony—money, family, a deal with the prosecutor | Yes, always—bias is never collateral |
| Sensory or mental defect | Couldn't perceive, remember, or narrate accurately | Yes |
| Character for untruthfulness | They're a liar generally—608 opinion/reputation, 608(b) specific acts, 609 convictions | Reputation/opinion witnesses yes; 608(b) specific acts no (cross only); convictions by the record |
| Contradiction | Some fact they asserted is just wrong | Only if the fact isn't collateral |
Lana testifies for the prosecution against Liv. Liv may show Lana said the car was green at her deposition (prior inconsistent statement), that Lana is Rosa's sister and Rosa is suing Liv (bias), that Lana wasn't wearing her glasses (sensory defect), that Lana's neighbors know her as a liar (608(a)), or that no crane was even on Shell Lane that day (contradiction).
Prior inconsistent statements—use vs. truth
Any prior inconsistent statement can impeach. It comes in substantively (for its truth) only if it was made under oath at a trial, hearing, or deposition—and the declarant now testifies subject to cross. Extrinsic proof requires giving the witness an opportunity to explain or deny, and never on a collateral matter.
Lana told her book club the light was green—impeachment only. Lana said it under oath at her deposition—impeachment AND substantive evidence that the light was green.
Convictions under 609: the chart
Can the conviction come in?
Is it a crime of dishonesty or false statement (crimen falsi)?
Automatic. Perjury, fraud, embezzlement—no balancing, felony or misdemeanor, any witness.
Is it a felony less than 10 years old?
Balancing. Ordinary witnesses: in unless 403 excludes. A criminal defendant-witness: in only if probative value outweighs prejudice—a thumb on the defendant's side.
More than 10 years since conviction or release?
Presumptively out. Admissible only if probative value substantially outweighs prejudice, with written notice.
Misdemeanors without dishonesty never come in
Liv's disorderly-conduct citation impeaches no one.
Rosa's 4-year-old perjury conviction—automatic. Noodle's 6-year-old burglary felony—balancing (tighter if Noodle is the defendant testifying). Lana's 12-year-old shoplifting misdemeanor—out.
Specific lies without convictions
Specific instances of untruthful conduct (lying on a job application, a false insurance claim) may be raised on cross-examination only, in the court's discretion. No extrinsic evidence—you're stuck with the witness's answer.
“Ms. Lana, didn't you fake a reference letter last year?” is fair cross. When Lana says no, Liv cannot call the reference to prove it—take the answer and move on.
Rehabilitation
Only after the attack: good-truthfulness character (reputation/opinion) is allowed only once truthfulness has been attacked; and a prior consistent statement rebuts a charge of recent fabrication or improper motive—if it was made before the motive arose—and then comes in substantively.
Liv's counsel says Lana invented her story after Rosa promised her money. Lana's identical account to Dr. Noodle—given before Rosa's promise—rebuts the charge and comes in for its truth.
The collateral-matter rule does the quiet work: you can cross on almost anything, but you can bring extrinsic proof only on things that matter—bias, capacity, non-collateral contradictions, qualifying priors. If the only value is “gotcha,” you're stuck with the answer.
Where the points are
The traps examiners actually set.
- Most tested
- 609's three tracks (crimen falsi automatic; recent felony balancing; 10-year staleness); prior inconsistent statements impeaching vs. coming in substantively; bias always provable extrinsically.
- Classic traps
- Extrinsic proof of 608(b) specific acts (never); bolstering before any attack; a prior consistent statement made after the motive arose; treating any misdemeanor as impeachment material; forgetting you may impeach your own witness.
Keep going: Privileges & Waivers quick chat Evidence Attack Sequences Hearsay deep dive Impeachment MEE guide