Witness testimony is a key source of evidence in trials. As such, the Federal Rules of Evidence have developed several rules to regulate the use of testimonial witnesses’ behavior. In this module, we’ll address those rules, learning about the general requirements for witnesses, as well as the requirements for expert and lay opinion testimony. We’ll then cover the treatment of witnesses, including the guidelines for leading questions, what happens when a witness forgets something and witness impeachment.
The Requirement of Competency
Under Federal Rule 601, “every person is competent to be a witness unless these rules provide otherwise.” The trial court has the discretion to decide whether a witness is competent, but every person is presumed to be competent. Competency is not a test of credibility or believability. It simply asks whether a witness can give the judge or jury information in a usable manner. The rule is very inclusive and favors permitting witness testimony. The Advisory Committee’s Note, which accompanies the rule and aids in its interpretation, says that a “witness wholly without capacity is difficult to imagine.” It is for the trier of fact (such as the jury) to determine how credible testimony is and how much weight it should be given.
A court may find a witness incompetent if he suffers from mental deficiency to the point that his testimony would be useless to the jury. This is rare, however. In U.S. v Blankenship, the prosecution’s key witness admitted to the jury that she was a drug addict and that her drug use occasionally caused her to hallucinate. The defendant claimed that because of the witness’s admission to drug use, she was incompetent. The appeals court disagreed, holding that witnesses are generally to be considered competent as long as they have personal knowledge of a matter and can state that they will speak truthfully.
Children are also generally considered competent to testify as long as the child shows the ability to understand questions, the difference between truth and falsity and the importance of telling the truth.
Under Rule 602, a witness may testify as to a matter only if evidence is introduced sufficient to support a finding that she has personal knowledge of the matter. More simply, she must have observed the facts that she is testifying to with her own senses. The witness doesn’t have to be absolutely certain of the facts she witnessed to satisfy the personal knowledge requirement. All that’s needed is enough testimony for a reasonable juror to find that the witness perceived the event. Additionally, “perfect” knowledge isn’t required, and a witness’s testimony isn’t excluded under Rule 602 simply because she can’t recall specific dates or if she testifies to having memory problems.
To testify, a witness must give an oath or affirmation to testify truthfully. Some courts may use Bibles or have the witness raise her hand before taking the oath. The only requirement is that the oath must be delivered in a way that conveys the witness’s duty to testify truthfully. For example, in State v. McClain, one of the witnesses was six years old. Rather than administering a traditional oath, before the child testified the judge asked the child, “These gentlemen are going to ask you some questions. Are you going to tell them the truth?” The child nodded in agreement. The judge then asked the child “Will you promise me you will tell them the truth?” The child again nodded in agreement. The appellate court held this was a proper oath, noting that an oath must be presented and delivered in a way that is appropriate for the witness. In this case, the child would not have understood the meaning of a wordy, more traditional oath, but understood the idea of promising to tell the judge the truth. Thus, it was an appropriate oath.
The rules of evidence generally disfavor testifying as to opinion, as evidence is supposed to supply facts and triers of fact are supposed to make the inferences. Still, opinions are allowed where:
- The opinion is based on the witness’s own perception;This means that the opinion must be based on the witness’s first-hand knowledge of the evidence.
- The opinion clarifies the witness’s testimony or is helpful in determining a fact at issue in the case;and
- The opinion is not based on scientific, technical, or other specialized knowledge.
For example, a witness may testify that, in his opinion, the car was driving too fast or the person was acting as though she were drunk. These are every-day opinions that laypeople can derive from their observations.
“Expert” witnesses are given more latitude to give their opinions. To qualify as an expert, a witness must possess specialized information on a topic that is derived from knowledge, skill, experience, training, or education. The expertise need not be directly related to the subject matter of the case. For example, in Rauch v. Mike-Mayer, the plaintiff sued his surgeons after suffering unexpected consequences from a surgery. He called a neurology physician and an emergency medicine physician as expert witnesses. The defense argued that neither of these doctors were surgeons and thus weren’t “experts.” The court allowed both to give expert testimony, noting that both had specialized knowledge in the field of medicine derived from their education and professional practice. The court also pointed out that the jury can decide how much weight to give to the doctors’ testimony if the defense argues that their qualifications were weak.
An expert may provide opinion testimony if:
- The testimony will help the judge or jury understand some evidence or determine a fact at issue in the case. This is also called a “needs test” because it requires that the expert’s testimony be necessary for some purpose in the case;
- The testimony is based on sufficient facts or data;
- The opinion is formed using reliable principles and methods; and
- The expert reliably applied the methods or principles used to the facts of the case at hand.
In Daubert v. Merrell Dow Pharmaceuticals, the plaintiffs sued a pharmaceutical company that produced a drug that allegedly led to birth defects. The plaintiffs introduced expert testimony, but the testimony was based on animal testing rather than human testing. The defense objected, arguing that the experts’ testimony did not meet Rule 702’s reliability standard. The Supreme Court ruled that the experts’ testimony met the reliability standard and was admissible. The Court provided a five-factor, “flexible” test for a trial court to analyze when determining scientific evidence’s validity:
- Whether the technique can be or has been tested;
- Whether the technique has been subject to peer review and publication;
- The known or potential rate of error;
- The existence and maintenance of standards in the particular field; and
- The degree to which the technique has been generally accepted in the scientific community.
Federal Rule 703 provides that an expert may base an opinion on facts or data that the “expert has been made aware of or personally observed.” Rule 703 also allows an expert to rely on information that isn’t otherwise admissible at trial, such as hearsay, if other experts in that field would “reasonably rely on those kinds of facts or data in forming an opinion on the subject.” For example, in United States v. Bramlet, the Seventh Circuit Court of Appeals held that a psychiatrist can base testimony on recorded observations of hospital staff members. Even though it’s hearsay, this is the type of information upon which psychiatrists routinely rely.
We’ll next turn to how a witness may be treated when testifying by addressing the rules regarding leading questions, cross-examination, faulty witness memory and witness impeachment.
Rule 611 addresses leading questions. A leading question is one that prompts or suggests a particular response. For instance, “You were at the park at 8 PM, right?” It is a leading question because it suggests an answer in its phrasing. Leading questions are generally not allowed on direct examination, which is when the witness’ proponent questions the witness. They are, however, allowed on cross-examination, where an attorney questions the other party’s witness. Leading questions are also allowed even on direct examination where the witness is “hostile” to that party or when the witness is the opposing party in a civil case.
Rule 611 also establishes the scope of cross-examination by only permitting questions on topics brought up in the direct examination. In one case- a prosecution for wire fraud arising from a scheme to file a fraudulent deed- the defendant explained on direct examination that his relationship with a co-conspirator consisted of her handling tax filings for court security officers and property management. On cross-examination, the government asked the defendant about his extramarital sexual relationship with the co-conspirator. The court found the cross-examination reasonably within the subject of the direct examination because of the suggestion on direct examination that the conspirators had only a business relationship.
It’s common for witnesses to have trouble recalling certain facts when on the stand. When this happens, Rule 612 provides two options. The first route is to refresh the witness’ recollection. This can only be done when a witness says he doesn’t remember something, as opposed to when he states he never knew something. The attorney can show the witness a document or object to jog his memory. The document or object does not itself need to be admissible. If the attorney wants to use a writing to refresh the witness’ memory, the writing must be made available to the opposing party, and that party must have the opportunity to cross-examine the witness about the writing.
The other option for an examining attorney is to use a past recorded recollection as a substitute for the witness’ present testimony. To use this method, an attorney can admit evidence of prior statements of the witness to fill in the information the witness has forgotten. The statement is admissible after the witness lays the foundation by establishing the circumstances of the communication, showing that it was a fair and reliable representation of the incident. For example, in Terry v. Jones, a battery victim had trouble recalling the details of her attack. The victim’s attorney wanted to use the statement she provided to the police in the police report as a past recorded recollection. The victim testified that she knew what happened during the attack at the time she made the police report, that she made the statement about three days after the incident, so it was still fresh in her mind, that she signed the statement and that its contents accurately reflected her knowledge at the time. The court ruled that the police report was admissible as a past recorded recollection.
Impeaching a Witness
Witness impeachment is a tool whereby an attorney provides evidence that calls a witness’ credibility into question. Rule 607 allows any party to impeach any witness, so an attorney can impeach his own witness.  There are many methods of impeaching a witness. One method, under Rule 608, is to attack a witness’ credibility by providing reputation or opinion evidence about the witness’ dishonesty. Once one side does this, the other party is then permitted to combat this accusation with reputation or opinion evidence of the witness’ truthfulness.
Evidence of past specific acts are not generally permitted to attack or strengthen a witness’s truthfulness. However, there are exceptions. First, evidence of past specific acts is permitted on cross-examination if it serves as evidence of the witness’ truthfulness or lack thereof. A second exception allows evidence of a past criminal conviction if the past crime was punishable by imprisonment for more than a year, though only if its probative value outweighs it prejudicial effect. Evidence of a past crime is also allowed, regardless of potential punishment, if the crime is one of dishonesty or making false statements.
The use of a past criminal conviction to impeach a witness is restricted by a 10-year limitation. If more than 10 years have passed since the witness’ conviction or release from confinement, the evidence is inadmissible unless its probative value substantially outweighs its prejudicial effect. When admissible, the party bringing up the conviction must give the adverse party advanced written notice of the intent to use the conviction to give the adverse party an opportunity to prepare for or protest the conviction’s usage.
Another method of witness impeachment is providing evidence of a prior statement made by the witness that is inconsistent with what the witness provides at trial. Evidence of a witness’ prior inconsistent statement is only admissible if the witness has a chance to explain or deny the statement and the opposing party has the opportunity to question the witness about the statement.
 Fed. R. Evid. 601.
 United States v. Blankenship, 923 F.2d 1110, 1116 (5th Cir. 1991).
 Fed. R. Evid. 601 Notes of Advisory Committee on Proposed Rules.
 United States v. Blankenship, 923 F.2d 1110, 1116-17(5th Cir. 1991).
 United States v. IMM, 747 F.3d 754, 769-70 (9th Cir. 2014).
 Fed. R. Evid. 602 Notes of Advisory Committee on Proposed Rules.
 United States v. Powers, 75 F.3d 335, 340 (7th Cir. 1996).
 Fed. R. Evid. 603.
 State v. McClain, 541 S.W.2d 351, 356 (Mo. Ct. App. 1976).
 Fed. R. Evid. 701.
 Fed. R. Evid. 701 Notes of Advisory Committee on Proposed Rules.
 Fed. R. Evid. 701.
 Fed. R. Evid. 702.
 Rauch v. Mike-Mayer, 783 A.2d 815, 821-22 (Pa. Super. Ct. 2001).
 Fed. R. Evid. 702.
 Daubert v.Merrell Dow Pharms., 509 U.S. 579, 593 (U.S. 1993).
 Fed. R. Evid. 703.
 United States v. Bramlet, 820 F.2d 851, 856 (7th Cir. 1987).
 Fed. R. Evid. 611.
 United Statesv. Brockenborrugh, 575 F.3d 726, 736 (D.C. Cir. 2009).
 Fed. R. Evid. 612.
 Fed. R. Evid. 803(5).
 United States v. Jones, 2003 CCA Lexis 272 at *18-19 (Navy-Marine Corp. Ct. Crim. App. 2003).
Fed. R. Evid. 607.
 Fed. R. Evid. 608.
 Fed. R. Evid. 609.
 Fed. R. Evid. 613.