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GPSolo Magazine

GPSolo May/June 2024: The Changing Face of Evidence

Impeachment Evidence: A Powerful Way to Discredit an Unfavorable Witness

Marina A Tucker

Summary

  • One of the most powerful and common ways to impeach a witness’s testimony is by confronting the witness with a prior inconsistent statement the witness made.
  • Demonstrating a witness’s bias, interest, or motive is a well-established means of impeachment.
  • To use impeachment evidence effectively, you must plan ahead and collect and preserve such evidence from the start of a case.
  • When you have a particularly sympathetic witness, it is important to tread carefully when impeaching that witness.
Impeachment Evidence: A Powerful Way to Discredit an Unfavorable Witness
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At trial, one powerful way to discredit an unfavorable witness is to present evidence that the witness should not be believed. Impeachment evidence is evidence designed to discredit the testimony of a witness. Under the Federal Rules of Evidence, any party, even the party calling the witness, may impeach the witness’s credibility. A witness’s testimony can be subject to impeachment for many reasons, including that the witness is lying, mistaken, biased, has a motive to testify in favor of one party, has an interest in the outcome of a case, or was somehow impaired such that the witness’s testimony is unreliable. This article addresses various types of impeachment evidence, considerations that should be given to its collection and preservation, ethical considerations related to using impeachment evidence, and the impact of impeachment evidence on the jury.

Types of Impeachment Evidence

1. Prior Inconsistent Statements

One of the most powerful and common ways to impeach a witness’s testimony is by confronting the witness with a prior inconsistent statement that the witness made. The most dramatic circumstance is a prior inconsistent statement that indicates that the witness is lying on the stand. If, at trial, a witness testifies inconsistently with a prior statement the witness gave, the Federal Rules of Evidence provide that the prior statement is admissible to impeach the witness’s credibility. If the witness’s inconsistent statement was not made under oath, it is only admissible to impeach the witness’s credibility. Under Federal Rule of Evidence 801(d)(1), a witness’s prior inconsistent statement is not hearsay if the prior statement was made under oath, which means that the statement is admissible not just to impeach the witness’s credibility but is also admissible to prove the truth of the matter asserted. For example, if a witness testifies during his deposition that the light was red but then at trial testifies that the light was green, his prior inconsistent statement is admissible both to impeach the witness’s credibility and to prove that the light was red.

If a witness’s prior inconsistent statement was not made under oath, it can still be used to impeach the witness’s character for truthfulness. Especially now that nearly everyone has one or more social media pages, one source of prior inconsistent statements may be a comment that a witness made on social media. In my practice, I have experienced numerous situations where a witness testified in a manner that is inconsistent with posts the witness publicly made on social media. Because most social media profiles include photographs of the person the profile belongs to, it can be easy to authenticate posts by simply asking witnesses to admit the profile belongs to them. This requires gathering information from the witnesses’ public social media pages prior to their deposition or testimony, saving them in a manner that preserves them, and ensuring that information such as dates, times, and the source is evident from the document. Preservation early on is particularly important because witnesses and/or parties to a case may delete posts from social media pages.

Another source of prior inconsistent statements that I see regularly in my practice defending personal injury cases is a party’s medical records. It is common for medical records to contain statements that a patient made, and these statements generally are easy to authenticate through the medical provider or the party that made the statement. Although I have had some parties claim that their medical provider wrote something inaccurately in a medical record, this has not been the norm in my experience. A medical record stating that a party just went on a weeklong hunting trip into the mountains can be used, for example, to impeach a witness’s credibility if the witness testifies that he cannot go hunting anymore.

Under Federal Rule of Evidence 613, it is not necessary to show the witness the prior inconsistent statement before examining the witness about the statement, but you must, upon request, show the statement to opposing counsel. Rule 613(b) also provides that extrinsic evidence of a witness’s prior inconsistent statement is only admissible if the witness is given the opportunity to explain or deny and the adverse party is given the opportunity to examine the witness about the statement. However, you can ask the witness about the statement before the witness has the opportunity to read the statement and perhaps come up with an excuse for it. The requirement that the witness be given the opportunity to explain or deny is why prior inconsistent statements are most often introduced during cross-examination of a witness.

2. Bias, Interest, or Motive

Although the Federal Rules of Evidence do not directly address impeachment through showing bias, interest, or motive of a witness to testify in a particular way, it is well established that these issues can be raised on cross-examination. Bias exists, for example, when a witness has a relationship with a party that causes the witness to favor or disfavor that party. In my practice, I have often seen a party’s friends or family members testify in support of that party. Friends and family, however, have a relationship with the party that leads them to be biased in favor of the party. This bias makes the witness’s testimony both less valuable and less harmful. I have also encountered witnesses who have a negative view of a party, for one reason or another, and appear to be biased against that party. Such a witness can be impeached based on that negative bias. Notably, bias can be proven by extrinsic evidence. If the witness denies bias, this bias can be shown to exist through the presentation of documents, another witness’s testimony, or a video, to name just three examples.

A witness can also be impeached by showing that the witness has an interest in the case’s outcome, such as when a witness stands to benefit from a particular outcome of a case and testifies in a manner that increases the likelihood of obtaining that benefit. Motive exists when a witness has a reason to testify in a certain way, often because of a history with one of the parties.

3. Bad Character for Truthfulness

Federal Rule of Evidence 608 allows you to attack a witness’s credibility by testimony about the witness’s character for truthfulness. Under Rule 608, you are limited to opinion and reputation evidence, and a proper foundation must be laid for a witness to testify regarding a witness’s reputation for untruthfulness. On cross-examination, you can ask a witness about specific instances of untruthfulness. If the witness denies these specific instances, however, you cannot introduce extrinsic evidence to contradict the witness’s testimony, and you are stuck with the witness’s answer. If the witness has a criminal conviction, Federal Rule of Evidence 609 provides an exception to the rule against the admissibility of specific instances of conduct. (See more below.) Notably, Rule 608 only allows the introduction of evidence of truthful character after the witness’s character for truthfulness has been attacked.

4. Prior Crimes

Federal Rule of Evidence 609 allows the use of prior crimes to impeach a witness’s credibility in certain circumstances. In criminal cases, when the witness is the defendant, a prior felony is admissible if the probative value on the issue of credibility outweighs the prejudicial effect. In criminal cases where the witness is not the defendant, and in civil cases, a prior felony is only admissible subject to the limitations of Federal Rule of Evidence 403, which provides that such evidence can be excluded, even if it is relevant, if its probative value is substantially outweighed by unfair prejudice. Rule 609 provides numerous limitations on how and when evidence of a prior criminal conviction is admissible.

Under the Federal Rule of Evidence, evidence of a witness’s prior crime involving dishonesty must be admitted if the elements of the prior crime require proving or the witness’s admitting a dishonest act or false statement. A prior conviction for fraud is one example of a crime involving dishonesty that would be admissible to impeach a witness’s credibility.

5. Prior Bad Acts

A witness can be impeached by specific instances of conduct that are probative of truthfulness. Prior bad acts, however, are not admissible to show propensity, only to attack a witness’s credibility. Additionally, you cannot introduce extrinsic evidence of a prior bad act that did not result in a conviction. As with an accusation of untruthfulness, if the witness denies the prior bad act, you are stuck with the witness’s answer.

6. Attacks on the Capacity of the Witness to Observe, Recall, or Relate

Evidence of a witness’s sensory or mental capacity is admissible when it is relevant to the credibility of the witness’s testimony. For example, evidence that a witness was drunk at the time he or she witnessed an incident is fair grounds to impeach a witness’s testimony and can be proven on cross-examination through extrinsic evidence. Another example could be if witnesses were not wearing their prescription glasses at the time they witnessed an incident and, therefore, could not see clearly.

Collection and Preservation of Impeachment Evidence

To use impeachment evidence effectively, you must plan ahead and collect and preserve such evidence from the start of a case. This means looking out for and taking note of any inconsistencies that you find in documents, pleadings, witness statements, discovery responses, and deposition testimony. In my practice as a civil defense attorney, the most common way that I collect and preserve impeachment evidence is through depositions and discovery.

Conducting discovery and gathering documents before taking depositions allow me to try to get a witness to authenticate documents or prior statements during the deposition. Once witnesses have authenticated a document during their deposition or admitted that they made a social media post, for example, that evidence is preserved on the record. Once witnesses testify under oath during a deposition, they cannot then testify at trial in an inconsistent way without damaging their own credibility. Documents produced in discovery may also contain prior statements, along with evidence of bias, motive, or interest. The discovery process also allows for the identification of witnesses who may be able to provide valuable impeachment evidence. As discussed above, I have also had success with gathering impeachment evidence from a witness’s public social media posts.

Ethical Considerations Involved in Using Impeachment Evidence

Before attempting to use impeachment evidence, you should take into account several important ethical considerations. The general rule is that a cross-examiner must have a good-faith basis to impeach a witness. American Bar Association Model Rule of Professional Conduct 3.4(e) provides that a lawyer shall not allude to any matter not supported by admissible evidence. This rule suggests that a cross-examiner must have a good-faith basis for the questions asked on cross-examination. When a lawyer asks questions, such questions contain insinuations, and even if the witness denies the question, the jury has already heard the insinuation. It would not be ethical to suggest that a witness has a prior fraud conviction, for example, if the lawyer does not have a good-faith basis to believe that the witness does, in fact, have a fraud conviction.

Along with the requirement that you have a good-faith basis to impeach a witness, in instances where the impeachment evidence is non-collateral (meaning that the evidence has a direct bearing on disputed issues in a case), you must be prepared to prove the impeachment. If you cannot prove the impeachment on a non-collateral issue, you will likely upset the judge and damage your own credibility with the jury. If the evidence relates to a collateral issue (meaning an issue that is not central to the case), you will likely be stuck with the witness’s answer and will not be able to present evidence to show that the witness is lying. In either case, however, you still must have a good-faith basis for the impeachment.

The Impact of Impeachment Evidence on the Jury’s Perception

How impeachment evidence impacts a jury’s perception can be difficult to determine with certainty unless jury members provide that information after the case is over. You can watch the jury members’ reactions and make guesses based on the jury’s verdict, but it can be hard to know for sure which evidence was most important to a jury.

In my experience, impeachment through prior inconsistent statements can have a strong impact on the jury’s perception of a witness’s credibility. This is particularly true when the prior inconsistent statement shows dishonesty on the part of the witness. A prior inconsistent statement given under oath can be compelling evidence to demonstrate that telling the truth is not important to the witness. In addition, when a prior inconsistent statement can be shown in writing, it is tangible and can be dramatic. If the jury believes that the witness is generally dishonest, the witness’s testimony as a whole is likely to be called into doubt.

Opinion and reputation evidence regarding a witness’s character for truthfulness is unlikely to carry a lot of weight with a jury. Jurors likely know that anyone can find someone to say something good or bad about them. Likewise, evidence that a witness mistakenly changed his or her testimony is unlikely to be effective in undermining the witness’s testimony because most people can relate to misremembering details or events.

When you have a particularly sympathetic witness, it is important to tread carefully when impeaching that witness. Aggressively suggesting that the witness is a liar, even if true, can backfire if the witness presents well, is likable, and is relatable. Jurors may react negatively if they perceive that you are bullying a sympathetic witness, even if, in so doing, you prove that the witness lied.

A Powerful Tool Requiring Significant Preparation

There is no doubt that discrediting a witness’s testimony with impeachment evidence can be a powerful tool at trial. Success requires planning ahead, preserving the evidence, authenticating it, understanding the rules, and considering which evidence to use against a given witness on a case-by-case basis. In short, the moment when you are able to discredit an unfavorable witness on the stand often comes after significant groundwork beforehand, but it is well worth the effort.

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