A witness who qualifies as an expert because of knowledge, skill, experience, training, or education may testify as an expert if scientific, technical, or other specialized knowledge will assist the judge, jury, or other factfinder to understand the evidence or determine a contested fact issue.

But there is no rigid formula for determining whether a particular witness is qualified to testify as an expert. Generally there must be a fit between the subject matter at issue and the expert witness’s familiarity with the subject matter. And this determination is made by the judge, who acts as a gatekeeper to only allow reliable expert witness testimony to be heard and considered by the judge or jury.

In North Carolina, expert witness testimony is governed by state statutes and case law. An individual may testify as an expert if they have the requisite knowledge, skill, experience, training, or education that will help the court understand the evidence or a fact in question. The determination of whether a witness qualifies as an expert is not based on a strict formula but rather on the relevance and reliability of the expert's knowledge to the subject matter of the dispute. The judge serves as a gatekeeper, assessing whether the expert's testimony is sufficiently tied to the issue at hand and whether it is based on a reliable foundation. This gatekeeping role is crucial to ensure that only pertinent and trustworthy expert testimony is presented to the jury or considered by the judge.