Jurors frequently make subjective assumptions about an expert witness regarding their credibility, which can substantially impact the outcome of a case. If the expert witnesses in a case do not come across as credible, then an attorney often has very little chance of winning at trial. Expert witnesses can be extremely important to the outcome of a case. In addition, credible witnesses and reliable witnesses are not necessarily the same thing. 

For an expert witness to be perceived as credible, they must demonstrate to be expert, objective, and communicative with their testimony. At Courtroom Sciences, our psychology experts can train expert witnesses on the nuance of remaining faithful to their opinions without appearing to be unreasonable, agitated, or condescending.

What makes an expert witness credible to the jury?

Jurors will likely consider three key factors: expertise, objectivity, and communicativeness. Credible expert witnesses should be able to continue to appear confident, articulate, and non-defensive when being attacked by the attorney on the other side. 

#1: Expertise   

An expert witness should have the knowledge and experience to speak with authority on the issues of the case. That likely includes having the requisite education credentials, specialties, and experience. However, the juror’s perceptions of the witness's expertise are just as important as these qualifications. Accuracy, consistency, perceptiveness, and diligence are four significant factors that may affect how a jury views the expertise of your expert witness. 

There are methods that attorneys can utilize to help expert witnesses demonstrate these facets of expertise:

●  Accuracy - use precision in measurement, assessment, analysis, and language.

●  Diligence - demonstrate thoroughness and the ability to apply themselves entirely to the consummation of a given task.

●  Perceptiveness - have a broad, unconstrained awareness of the parameters of a given problem.

●  Consistency - effectively utilizing the qualities of accuracy, diligence, and perceptiveness across various situations.

#2: Objectivity   

Most jurors expect a given expert witness to favor the side that retained them, also likely assuming that an expert witness will be biased toward that side. However, to be found credible by a jury and for an expert witness to be able to influence a jury, they need to appear objective. In most cases, the jury expects a credible expert witness to be able to acknowledge that there can be more than one side to an issue.

For an expert witness to demonstrate their objectivity to a jury, they need to empirically show to the jury why one of those conflicting views is, in fact, most probably correct. An expert witness’ preference for the defendant’s case should be completely a function of scientific evidence and rigorous application of their preexisting expertise, indicating to the jury their ability to equally consider two or more conflicting interpretations of a given problem.

#3: Communicativeness   

Another factor that influences an expert witness’s perceived credibility is the ability to clarify arcane or esoteric issues so that they are comprehensible to others. The language and jargon that feels natural to an expert witness may be hard for someone else to grasp. A communicative witness should be sensitive to the fact that what is simple to them may be difficult for others, specifically the untrained juror. 

Beyond that, to appear credible, the communicative expert witness must give the impression that they care whether others understand. Such caring may be reflected in the choice of terminology the expert witness selects to explain or make analogies, their use of visual aids, and the pauses they take to give jurors time to assimilate the information presented. It may also be reflected in the expert witness’s eye contact, speech rate, tone, volume, articulation, vocal inflections, and even posture. Expert witnesses should remember that communicativeness is also influenced by non-verbal attributes such as attire, mannerisms, and facial expressions.  

Expert witnesses can be a critical component of many cases, as they provide expertise and help jurors understand complex and nuanced information. It is equally important for attorneys to prepare their expert witnesses to maximize their effectiveness. At Courtroom Sciences, we train expert witnesses on the nuance of remaining faithful to their opinions without appearing to be unreasonable, agitated, or condescending.

Learn more about witness training with CSI.

Key Takeaways

●  Expert witness credibility can significantly impact trial outcomes. 

●  Credible witnesses and reliable witnesses are not necessarily the same thing. 

●  Three key factors for witness credibility include expertise, objectivity, and communicativeness.

●  Courtroom Sciences trains expert witnesses on the nuance of remaining faithful to their opinions without appearing to be unreasonable, agitated, or condescending.