News 04.12.17

Raising the Bar: Missouri’s New Daubert Law

Expert Opinions: The Old Missouri Standard

Admissibility of expert opinion is governed by Section 490.065, RSMo. Until the new legislation becomes effective on August 28, 2017, it reads:

  1. In any civil action, if scientific, technical or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education may testify thereto in the form of an opinion or otherwise.
  2. Testimony by such an expert witness in the form of an opinion or inference otherwise admissible is not objectionable because it embraces an ultimate issue to be decided by the trier of fact.
  3. The facts or data in a particular case upon which an expert bases an opinion or inference may be those perceived by or made known to him at or before the hearing and must be of a type reasonably relied upon by experts in the field in forming opinions or inferences upon the subject and must be otherwise reasonably reliable.
  4. If a reasonable foundation is laid, an expert may testify in terms of opinion or inference and give the reasons therefor without the use of hypothetical questions, unless the court believes the use of a hypothetical question will make the expert's opinion more understandable or of greater assistance to the jury due to the particular facts of the case.

The statute was introduced in an effort to establish a uniform standard for Missouri courts, which had previously utilized various standards. The Missouri Supreme Court first applied the “Frye test” in a criminal matter in 1972,[1] requiring “general acceptance” of the expert’s methodology in order for an opinion based thereon to be admissible.[2] The test’s general acceptance standard evolved to a more refined “wide scientific approval” standard in 1980,[3] which was first applied in a civil matter in 1985.[4] Even after Section 490.065 was enacted in 1989, state courts continued to follow hybridized standards until 2003.[5]

The statute’s inconsistent application may be partly explained by its applicability to only “civil actions,” which leaves unresolved the issue of expert testimony in other proceedings (e.g. administrative hearings). In addition, the original language of section 490.065 partially mirrors Federal Rules of Evidence 702 and 703. Thus, when the Supreme Court of the United States decided Daubert v. Merrell Dow Pharmaceuticals — holding that FRE 702 superseded the Frye test [6] — Missouri courts struggled to decide whether section 490.065 similarly superseded state court decisions endorsing the Frye standard. It was not until 2003 that the Missouri Supreme Court finally reconciled Daubert with section 490.065, holding that the statute controlled admissibility of expert testimony and abrogating cases following Frye and other hybrid approaches.[7]

In so holding, however, the Court acknowledged that Daubert and its progeny were only instructive to the extent that the language of section 490.065 mirrored that of FRE 702 and FRE 703. Insofar as the federal rules diverge from the Missouri statute, section 490.065 must control. The major distinction lies in Missouri’s requirement that the facts on which an expert bases an opinion “must be of a type reasonably relied upon by other experts in the field.” By contrast, FRE 702 and FRE 703 generally do not require definition of the expert witness’ “relevant scientific community.” Rather, the federal rules principally ask whether expert opinions are the “product of reliable principles and methods.”

Critics of section 490.065 charge that the “relevant scientific community” merely echoes the Frye test of “general acceptance,” prioritizing this one outdated factor to the exclusion of other considerations. Although the Missouri Supreme Court purportedly abrogated cases following Frye, as practical matter, the statute re-enshrines the Frye test as a threshold matter and admits expert testimony — even “junk science” — that somehow evades any other consideration of its reliability.

Expert Opinions: The Daubert Standard

In federal court, the standard espoused in Daubert[8] provides the rules of admissibility regarding expert witness testimony. The Supreme Court in that case held that Federal Rule of Evidence 702 did not incorporate the Frye test of “general acceptance” in assessing the admissibility of scientific expert testimony; rather, Daubert held that FRE 702 incorporated a more flexible reliability standard, of which “general acceptance” is but one of several factors.

By its own terms, FRE 702 states that 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:

(a) the expert’s scientific, technical, or other specialized knowledge will help the trier of fact to understand the evidence or the 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 has reliably applied the principles and methods to the facts of the case.

When applying FRE 702 to the issue of admissibility with regard to expert testimony, a judge will make a preliminary assessment of whether an expert’s scientific testimony is based on reasoning or methodology that is scientifically valid and can properly be applied to the facts at issue. Under Daubert, the factors that a judge may consider in determining whether the methodology is valid are:

(1) whether the theory or technique in question can be and has been tested;
(2) whether it has been subjected to peer review and publication;
(3) its known or potential error rate; and
(5) whether it has attracted widespread acceptance within a relevant scientific community.

Federal courts have further refined the Daubert standard’s emphasis on scientifically valid methodology. In General Electric v. Joiner, for example, the Supreme Court held that a judge may exclude expert testimony when logical gaps appear between an expert’s conclusion and the evidence relied on in reaching it,[10] thus preserving Daubert’s simultaneous demands for judicial discretion and sound methods. Further, in Kumho Tire v. Carmichael, the Court clarified that the trial judge, as evidentiary gatekeeper, must ensure the reliability and relevance of all expert testimony, holding that Daubert applied to all expert testimony, whether scientific or non-scientific.[11] In these and subsequent decisions, federal courts and a majority of states have maintained Daubert’s complementary paradigm bases governing admissibility of expert opinions: judicial flexibility in the determination of scientific validity.

Expert Opinions: The New Missouri Standard

The revisions to section 490.065, RSMo., essentially adopt the Daubert approach, raising the standard of admissibility for expert opinions. In revising the law, Missouri joins 39 other states in adopting the higher standard, including its fellow Eighth Circuit states of Minnesota, South Dakota, Iowa, Nebraska and Arkansas. The decisions of those states’ courts will be instructive in interpreting and applying the new rules; further, because the new statute mirrors Federal Rules of Evidence 702, 703, and 704, Missouri courts may draw guidance from the Eighth Circuit and Missouri’s own federal district courts. 

The revised portion of section 490.065 that applies to most civil cases reads:

  1. In all actions except those to which subsection 1 of this section applies:
(1) 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:
(a) The expert’s scientific, technical, or other specialized knowledge will help the trier of fact to understand he evidence or to determine a fact in issue;
(b) The testimony is based on sufficient facts or date;
(c) The testimony is the product of reliable principles and methods; and
(d) The expert has reliability applied the principles and methods to the facts of the case …

This new version replaces the “relevant scientific community” standard with specific criteria that allows the trial court to assume its role as gatekeeper of expert testimony. Rather than hewing to the Frye test’s singular threshold consideration, the new statute empowers and requires the trial court to find that all expert testimony is based on sufficient facts or data, results from reliable principles and methods, and applies those principles and methods reliably to the specific case.

It is important to note that the standard governs the expert opinion and not the underlying facts and data relied upon. The legislative summary of the new law indicates that “such facts or data need not be admissible for the opinion to be admitted,” and an expert may “state an opinion” before testifying to the underlying facts or data.[12]


Missouri trial judges calling evidentiary balls and strikes will face a newly-defined strike zone: wider in some ways, but narrower in others. On the one hand, the trial judge must consider several factors — not just the expert’s community — and determine whether the expert’s opinion is reasonably drawn from reliable data and methodology. These additional factors broaden the latitude of the trial judge’s discretion, suggesting a new frontier of litigation with unpredictable results. On the other hand, Missouri judges may now draw from a huge body of law in finding precedent which rests on sound legal reasoning; this broad base of precedent gives Missouri judges the freedom of relative certainty, suggesting greater uniformity of application and more predictable rulings on admissibility.  

Also of note is that Missouri’s new statute does not indicate how this new standard is to be litigated, i.e., by special hearings, pretrial motions, or trial objections. While the new law is silent on this point, in other jurisdictions, this contest occurs at a pretrial hearing (i.e. a Daubert hearing). Sometime at or near the close of discovery, when experts are all disclosed and the facts are as certain as they are likely to be without trial testimony, litigants will ask Missouri judges to determine whether or not the other side’s expert may properly be brought before the jury.  The remedy, that the expert’s opinion be excluded from the trier of fact’s consideration in part or in its entirety, is a drastic one in practical application. A case often rests squarely on the shoulders of an expert who can shore up the credibility of party witnesses and educate the jury on the science or practices underlying the claim or defense, and a successful attack on an expert can sink a case. The standard of review, “abuse of discretion”, still leaves Missouri state court judges some leeway to make those close calls, but now within a framework of jurisprudence which demands attention to reliability of the facts and methodology, which no doubt will demand more attention, and more time from the Court in hearings and briefing.  

What does that boil down to in simple terms?  While the statute is silent on how it shall be implemented, the Daubert hearing is now a live point of discussion in State Courts of Missouri. Daubert hearings will give litigants a chance to take a judge’s temperature before trial as to where and how far the judge is willing to let their experts go, subject to the governing law on experts which is continually in flux and so provides some cover. Importantly for early resolution, these hearings will give each side a chance to reach a leverage point, and come to agreement on resolution pretrial.

To read the passed bill, click here:

To read the comment, click here.

[1] State v. Stout, 478 S.W.2d 368, 371 (Mo. 1972).

[2] See Stout, 478 S.W.2d at 371 (applying Frye v. United States, 293 F. 1013, 1014 (D.C. Cir. 1923)).

[3] State v. Biddle, 599 S.W.2d 182, 191 (Mo. banc 1980).

[4] Alsbach v. Bader, 700 S.W.2d 823, 828 (Mo.banc 1985).

[5] See, e.g., Lasky v. Union Electric Co., 936 S.W.2d 797, 801 (Mo. banc 1997) (instructing trial court that Section 490.065 constituted guidance, but not mandatory authority); Bray v. Bi-State Dev. Corp., 949 S.W.2d 93, 98 (Mo.App. E.D. 1997) (applying Frye); Whitman’s Candies, Inc. v. Pet Inc., 974 S.W.2d 519, 528 (Mo.App. W.D. 1998) (applying Frye and Daubert); Long v. Missouri Delta Medical Center, 33 S.W.3d 629, 642-43 (Mo.App. S.D. 2000) (applying Frye to scientific evidence and Section 490.065 to non-scientific evidence).

[6] See Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579, 589 (1993).

[7] State Board of Registration for the Healing Arts v. McDonagh, 123 S.W.3d 146, 151-53 (Mo. banc 2003).

[8] See Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (1993).

[9] Daubert, 509 U.S. at 593-94.

[10] General Electric Co. v. Joiner, 522 U.S. 136, 146-47 (1997).

[11] Kumho Tire Co. v. Carmichael, 526 U.S. 137, ___ (1999).

[12] HB0153T, Mo. Leg. Reg. Sess. 2017.