What Makes an Expert Testimony Credible?
In both civil and criminal trials, a lawyer may decide to use an expert witness to testify. An expert is typically someone with a professional background in a given subject matter who brings his knowledge and facts to the case. While many people can be considered an "expert" on a given topic, an expert witness's credibility is determined by the court before the witness can testify at a trial.
Other People Are Reading
-
Significance
-
In a trial, the expert witness is a person who has a specific background in something pertaining to the case. Called to the stand to give her expert opinion, the testimony is supposed to help the jurors understand what a professional has to say about the matter at hand. Experts are often doctors, scientists or forensic analysts, but anyone can be acknowledged by the court as an authority on a subject.
The expert's testimony cannot be based on hearsay or personal opinion; rather, she must use educated statements, factual documents and analysis to backup her testimony.
Expertise
-
An expert testimony is considered credible because the jury is relying on a professional person to uphold his oath and give his expert opinion on the case. For instance, a doctor may be called to testify in a paternity suit or murder trial depending on his area of knowledge and the ability to back up his opinions with facts and educated responses.
-
Attitude
-
As much as a jury likes to hear factual evidence, they also may be affected by an expert's demeanor. If the individual testifying comes off as rude, defensive, condescending, inconsistent or manipulative, the jury will likely be less inclined to take the testimony into account.
The expert should approach the subject matter and the jury with a professional attitude and base his answers on facts.
Background
-
Having an extensive background in a certain subject matter and making the jurors aware of that can help an expert's credibility. However, speaking in layman's terms, using language that the jury can understand while giving opinions and facts can help build an expert's credibility as well.
In addition, a person who performs well under the pressure of a cross examination, without changing her opinion, will hold more credibility.
Considerations
-
In most states, before a person is allowed to testify as an "expert" he is subject to either the Frye test, which requires that the expert's opinion be derived from a basic principle believed by the majority of experts in their field, or the Daubert test, which expands upon the Frye test, allowing the judge final decision over whether expert testimony is based on scientific knowledge and uses true method and reasoning.
-
