Ariz. R. Evid. 702

As amended through August 22, 2024

Rule 702 - Testimony by Expert Witnesses

A witness who is qualified as an expert by knowledge, skill, experience, training, or education may testify in the form of an opinion or otherwise if the proponent demonstrates to the court that it is more likely than not that:

(a) 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;

(b) the testimony is based on sufficient facts or data;

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

(d) the expert's opinion reflects a reliable application of the principles and methods to the facts of the case.

Ariz. R. Evi. 702

Amended Sept. 8, 2011, effective 1/1/2012; amended Aug. 24, 2023, effective 1/1/2024.

Comment to 2024 Amendment

Rule 702 was amended effective January 1, 2024, to conform to the changes made to Federal Rule of Evidence 702 that took effect on December 1, 2023. These changes are intended to clarify the standard of proof that the proponent of expert testimony must satisfy as well as to address the issue of expert overstatement. Rule 702 permits "cold" experts to offer general, educative testimony to help the trier of fact understand evidence or resolve fact issues. State v. Salazar-Mercado, 234 Ariz. 590, 592 ¶ 6 (2014).

COMMENT TO 2012 AMENDMENT

The 2012 amendment of Rule 702 adopts Federal Rule of Evidence 702, as restyled. The amendment recognizes that trial courts should serve as gatekeepers in assuring that proposed expert testimony is reliable and thus helpful to the jury's determination of facts at issue. The amendment is not intended to supplant traditional jury determinations of credibility and the weight to be afforded otherwise admissible testimony, nor is the amendment intended to permit a challenge to the testimony of every expert, preclude the testimony of experience-based experts, or prohibit testimony based on competing methodologies within a field of expertise. The trial court's gatekeeping function is not intended to replace the adversary system. Cross-examination, presentation of contrary evidence, and careful instruction on the burden of proof are the traditional and appropriate means of attacking shaky but admissible evidence.

A trial court's ruling finding an expert's testimony reliable does not necessarily mean that contradictory expert testimony is not reliable. The amendment is broad enough to permit testimony that is the product of competing principles or methods in the same field of expertise. Where there is contradictory, but reliable, expert testimony, it is the province of the jury to determine the weight and credibility of the testimony.

This comment has been derived, in part, from the Committee Notes on Rules--2000 Amendment to Federal Rule of Evidence 702.

HISTORICAL NOTE

Source:

Federal Rules of Evidence, Rule 702.