CHAPTER 71

Senate Bill No. 398

An Act concerning the rules of evidence; relating to testimony in the form of opinion; requiring a proponent to demonstrate that it is more likely than not that certain specialized knowledge will help the trier of fact to understand the evidence before certain qualified witnesses may testify; amending K.S.A. 60-456 and repealing the existing section.

Be it enacted by the Legislature of the State of Kansas:

Section 1. K.S.A. 60-456 is hereby amended to read as follows: 60-456. (a) If the a witness is not testifying as an expert, the testimony in the form of opinions or inferences is limited to such opinions or inferences as the judge finds an opinion is limited to one that is:

(1) Are Rationally based on the perception of the witness;

(2) are helpful to a clearer clearly understanding of the testimony of the witness or determining a fact in issue; and

(3) are not based on scientific, technical or other specialized knowledge within the scope of subsection (b).

(b) If scientific, technical or other specialized knowledge will help the trier of fact to understand the evidence or to determine a fact in issue, A witness who is qualified as an expert by knowledge, skill, experience, training or education may testify thereto in the form of an opinion or otherwise if the proponent demonstrates to the court that it is more likely than not that the:

(1) The Expert’s scientific, technical or other specialized knowledge will help the trier of fact to understand the evidence or to determine a fact in issue;

(2) testimony is based on sufficient facts or data;

(2)(3) the testimony is the product of reliable principles and methods; and

(3)(4) the witness has reliably applied expert’s opinion reflects a reliable application of the principles and methods to the facts of the case.

(c) Unless the judge excludes the testimony, the judge shall be deemed to have made the finding requisite to its admission.

(d) Testimony in the form of opinions or inferences otherwise admissible under this article is not objectionable because it embraces the ultimate issue or issues to be decided by the trier of the fact.

Sec. 2. K.S.A. 60-456 is hereby repealed.

Sec. 3. This act shall take effect and be in force from and after its publication in the statute book.

Approved April 7, 2026.