Forensic, General & Medical
Expert Witnesses

What Factors Influence Jurors when Evaluating the Testimony of Expert Witnesses

     By HG.org

Expert Witness testimony usually has a steep basis in fact, method and process with scientific data and other evidence as a foundation. This may influence how the jurors evaluate the testimony, but other factors may exist that alter their perceptions.
The credibility of an expert witnessí testimony usually is based on confidence in the facts, understanding the evidence and how the expert presents the details. How much reliance on the professionalís data may be seen through observations, but some jurors only think about what has been said and then may deliberate without any outward signs. There are studies that have been conducted to determine the credibility and faith in an expertís testimony, and these tests may provide more insight into how a juror makes his or her vote for guilt or innocence with these expert witnesses accounted for in the case.

Certain factors that affect an expert witness providing testimony may be opposing lawyers completing aggressive and extensive questioning when cross examining him or her. There could be repercussions in the defendant seeking litigation for vindictive reasons. When some of these situations come to light, it could harm the professionalís credibility with jurors. However, when the expert witness is prepared by the lawyer that hired him or her, he or she may be able to increase confidence in his or her testimony. This shows that he or she has knowledge and an understanding of the evidence even when questioned fiercely.

Accuracy and Credibility

When the expert witness speaks with confidence and appears to have a working knowledge of the subject matter, he or she may be viewed as accurate and believable due to his or her presence and demeanor. Many jurors base credibility of an expert witnessí testimony on whether he or she is believable, has good credentials based on what the individual juror knows and whether each person likes him or her. This is the trust that these jurors potentially place in the person. This means that if the professional is well-attired, has a nice, calm and charming presence and has presented the information in a manner they understand, the members of the jury panel potentially put more faith in the testimony than if these qualities are lacking.

Other factors that play an important role may include if the expert is from the same neighborhood or community as the jurors, has previously testified in a similar case, have provided psychological therapy to the client or something similar and have not been paid for previous testimony. Some of these are in contradiction to the services of an expert witness, as many of these persons are hired for the case specifically. However, for the testimony to be more effective and considered credible, the jurors often place self-sacrificing characteristics above knowledge and experience per various studies into these matters.

Confidence in the Expert Witness

When the expert witness has confidence in his or her own abilities and the evidence being tied to the defendant or plaintiff, many jurors are positively influenced in believing he or she has the testimony necessary for proving or rejecting the claim. This is often demonstrated through self-assurance and a general ability of standing in the witness stand with an air of confidence. However, in contrast to that is the demeanor of arrogance. This will quickly turn the jurors against the expert witness. This means the professional needs to be confidence, have belief in his or her knowledge and experience but remain humble or trustworthy.

Confidence is usually observed through both verbal and nonverbal cues such as a lack of nervousness and an easy flowing description of certain aspects of the case. Jurors may lose faith in the expert if he or she starts twitching, stuttering or speaking nonsense. A quivering voice is best left out of the courtroom unless the testimony is so driven with emotion due to the circumstances that it may move the jury panel. It is both the words and the behavior that each juror may zero in on when placing weight and faith in the testimony of an expert witness.

The Expert Witnessí Influence

While many of the factors are due to how the expert witness behaves in the courtroom, some of the confidence and faith placed in him or her is due to his or her inherent abilities in testifying or presenting evidence. If he or she is able to speak in a soothing manner, or his or her words are charming, this could convince the jurors to listen more carefully. Eye contact and connecting with the jury panel is important, and could increase the ability to influence the jurors.

Copyright HG.org


While every effort has been made to ensure the accuracy of this publication, it is not intended to provide legal advice as individual situations will differ and should be discussed with an expert and/or lawyer.

Find an Expert Witness