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 Kansas, expert witnesses are individuals who, due to their knowledge, skill, experience, training, or education, may provide testimony in legal proceedings if their specialized knowledge can help the judge or jury understand the evidence or resolve a disputed fact. The qualification of an expert witness is not determined by a strict formula; rather, there must be a relevant connection between the expert's expertise and the subject matter of the case. The decision as to whether a witness is qualified to testify as an expert is made by the presiding judge. This judge serves as a gatekeeper, ensuring that only reliable expert testimony is presented to the decision-makers in the trial. This approach is consistent with the goal of maintaining the integrity of the legal process and ensuring that the fact-finders are well-informed by credible and pertinent expert insights.