1. Generally speaking, the rules of evidence are the same for cross-examination as direct examination.

2. There are some differences in the rules on the form of proper questions and answers.
a) Leading questions are allowed on cross-examination, as long as they are not misleading
b) The rule against repetition is relaxed, at least for evasive or uncooperative witnesses. Attorneys may "sift" a witness believed to be evasive or lying, and repeat questions until the witness provides a clear answer.
c) If the examining attorney asks a simple leading question, s/he has a right to require the witness to give a simple yes/no answer. This "right" is difficult to enforce.
d) If the examining attorney asks a misleading question, where a yes/no answer would not be the complete truth, the witness has the right to explain it.

3. One typical problem involves drawing a line between permissible repetition used when witnesses are hostile, evasive or lying, and impermissible repetition used to badger a witness who is trying to be cooperative but you just don't like the answer. In the following example, some judges would allow it, others would not, depending on their opinion whether the witness genuinely did not remember or was being evasive.
Q: Was Joe drunk? A: I don't know.
Q: You don't know if Joe was drunk? A: That's right, I don't know.
Q: You were with Joe in a bar, right? A: Yes.
Q: Drinking? A: Yes
Q: And Joe was drunk, wasn't he? A: I don't know.
Q: Was that because you were drunk, too? A. No.
Q. Tell the truth. Weren't you both drunk?

4. The scope of direct examination is limited only by the rules of relevancy. The scope of cross may be more limited. Rule 611(b) says that cross-examination "should" be limited to the subject matter of the direct plus matters affecting the credibility of the witness. The use of "should" puts the scope of cross within judicial discretion. many judges allow broad scope; others more strictly limit cross to issues raised on direct and impeachment.


1. FRE 607 says that impeachment is proper, but does not say what kinds of evidence may be used to impeach. Rules 608 (character), 609 (criminal conviction) and 610 (religious beliefs) address some but not all of the various types of evidence relevant to impeach, so you have to rely on case law and tradition. Typically, you can impeach a witness with evidence of:
a) A personal, social or political bias relevant to the case
b) An interest in the outcome
c) A prior criminal conviction
d) A prior act of dishonesty or false statement
e) Untruthful character
f) Inconsistent statements
g) Drug, alcohol or mental impairment
h) Poor eyesight or hearing
i) Poor opportunity to observe the events

2. It is always proper to impeach a witness. Therefore, invoking the impeachment rules is usually a response to an objection. For example:

a) Q: Didn't you used to date the defendant back in college 10 years ago?
Objection: Irrelevant.
Response: Relevant to impeach the witness for bias.

b) Q. Weren't you and the defendant both members of a criminal gang called the Vice Lords when you were all convicted of perjury for lying to protect each other?
Objection: Rule 403.
Responses: Significant probative value to impeach the witness for bias, and the conviction is admissible under Rule 609.

c) Personal injury case against cab driver and taxi company. The plaintiff and the cab driver settle, and the driver testifies for plaintiff against the taxi company that the car's brakes were bad.
Q: You were originally sued as a defendant but settled with plaintiff, didn't you?
Objection: Rule 408 makes settlements inadmissible.
Response: Not offered to show liability, but to impeach the witness for bias and self-interest.

d) Q: Would you say that the plaintiff has a tendency to lie and exaggerate?
Objection: Character evidence.
Response: Rules 404 and 608(a) permit evidence of a witness's character for lying to impeach.

e) Q: You cheated on your exams in college, didn't you?
Objection: Irrelevant character evidence.
Response: Rule 608(b) permits evidence of a specific acts of bad character showing untruthfulness.

f) Q: "Did you hear Detective Mark Fuhrman say "I hate O.J. Simpson and all black people, so I have planted evidence against him?"
Objection: Hearsay
Response: Not for truth, but to show bias.

g) Q: [From "The Verdict"] Today you testified that the patient ate 1 hour before admittance, but on this hospital report, didn't you write a "nine?"
Objection: The hospital report is hearsay.
Response: Not for its truth, but to impeach as prior inconsistent statement.

3. Impeachment is proving that a witness's testimony is unreliable and may be wrong. The process involves bringing out the facts that reduce the jury's confidence in the accuracy of the witness's testimony.

4. Distinguish impeachment from contradiction. Impeachment is casting doubt on the reliability of a particular witness. Contradiction is casting doubt on the reliability of the other side's factual case.

5. Impeachment evidence is tangential to the main facts of the case and is often prejudicial under Rule 403 as either confusing the issues or arousing emotions. Impeachment is therefore usually restricted to the cross-examination of the witness being impeached and may not be proved by extrinsic evidence (documents and other witnesses), and may be curtailed at the judge's discretion.

6. A witness's testimony may be unreliable for two quite different reasons:
a) The witness may be deliberately lying and therefore knowingly committing the crime of perjury -- it happens, but people willing to commit crimes in front of judges are rare.
b) More likely, the witness is trying to tell the truth, but happens to be mistaken because he or she saw the event incorrectly, has forgotten parts, misinterpreted what the witness saw, etc.

7. Impeachment does not consist of asking the witness directly to admit to being a cold-blooded liar or to admit that the witness has remembered something incorrectly. The liar will not admit being a liar, and the honest but mistaken witness will not know s/he is mistaken, so neither will admit to being wrong if asked.

8. So, impeachment is the process of proving circumstantial evidence that suggests to the jury a likelihood that the witness does not understand the need to tell the truth, is mistaken, or is lying.