The Daubert Test

December 01, 2000-By Mary A. Kalmink

In Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 113 S. Ct. 2786, 125 L. Ed. 2d 469 (1993) ("Daubert I"), the U.S. Supreme Court changed the standard for admissibility of expert testimony. Prior to Daubert, the standard was the Frye test: Scientific evidence was admissible if it was based on a scientific technique generally accepted as reliable in the scientific community. Frye v. United States, 293 F. 1013, 1014 (D.C. Cir. 1923).⁽¹⁾ Expert testimony was admitted simply by virtue of the expert's credentials, experience, skill and reputation. Any deficiencies or flaws in the expert's conclusions would be exposed through cross-examination.

Under Daubert, the admissibility of expert testimony is to be more rigorously scrutinized by the trial judge to determine whether it meets the requirements of Fed. R. Evid. 702, which provides:

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 a expert by knowledge, skill, experience, training or education, may testify thereto in the form of an opinion or otherwise.

The Daubert Court assigned trial judges a "gatekeeping" role to determine as a preliminary matter whether the proposed scientific testimony is both reliable and relevant. Daubert, 509 U.S. at 597. Recently, the Supreme Court broadened that role and test to include expert testimony based on technical and other specialized knowledge. Kumho Tire Co., Ltd. v. Carmichael, ___ U.S. ___, 119 S. Ct. 1167, 1174, 143 L. Ed. 2d 238 (1999). Kumho was a product liability suit involving an allegedly defective automobile tire. Plaintiff's tire failure expert based his conclusions solely on a visual inspection of the tire. He intended to testify that, given the absence of at least two of four physical indicia of tire abuse, a defect in the tire must have caused the accident. This testimony was excluded because there was insufficient evidence of reliability of the expert's methodology.

A. Judge As Gatekeeper

On remand from the U.S. Supreme Court, the Ninth Circuit embarked on its gatekeeping task with a certain amount of trepidation. Daubert v. Merrell Dow Pharmaceuticals, Inc., 43 F.3d 1311 (9th Cir. 1995) ("Daubert II"). Entering the "brave new world" of post-Daubert decision-making, the Daubert II court felt that having to determine the reliability of expert testimony put trial judges in "an uncomfortable position" with a "daunting" task before them. Id. at 1315-16.

The Second Circuit also cautioned trial judges against taking their gatekeeping role too far, for that "would elevate them to the role of St. Peter at the gates of heaven, performing a searching inquiry into the depths of an expert witnesses' soul-separating the saved from the damned. Such an inquiry would inexorably lead to evaluating witness credibility and weight of the evidence, the ageless role of the jury." McCullock v. H. B. Fuller Co., 61 F.3d 1038, 1045 (2nd Cir. 1995).

By contrast, other courts have whole-heartedly embraced the position of gatekeeper, delving deeply into scientific method and analysis. Such exercises have the blessing of the Supreme Court, which has conferred an extra measure of discretion on trial judges with regard to expert testimony. General Electric Co. v. Joiner, 522 U.S. 136, 143, 118 S. Ct. 512, 139 L. Ed. 2d 508 (1997). Thus, trial courts have extremely broad discretion in fashioning how to test an expert's reliability, in deciding whether and when to order special briefing or evidentiary proceedings, and in reaching their ultimate conclusions on the admissibility of expert testimony. Id. at 138-39, 143.

With this background, we turn to the guidance provided to trial judges in deciding whether expert testimony is reliable and relevant.

B. Reliability

1. Scientific Evidence

The Daubert I Court suggested a number of non-exclusive factors to aid in determining whether an expert's methodology is reliable:

1. Whether the theory or technique has been or can be tested, i.e. falsified;

2. Whether the theory or technique has been subjected to peer review and publication;

3. Consideration of the known or potential rate of error of the method used;

4. The existence and maintenance of standards controlling the techniques operation; and

5. Whether the theory or method has been generally accepted by the scientific community.

Daubert I, 509 U.S. at 593-94.

The Daubert II Court offered further guidance in applying these factors, stressing that in determining reliability, courts must analyze not what the experts say, but what basis they have for saying it. Daubert II, 43 F.3d at 1316. The most persuasive factor for the Daubert II Court was whether the expert had conducted research independent of the litigation or whether the expert's opinions were developed expressly for the purpose of testifying. Id. at 1317. If, as is the case with the vast majority of expert testimony, that testimony was developed solely for litigation purposes, the expert's qualifications (no matter how impressive), conclusions, and bald assurances of validity and reliability are not enough to pass muster under Daubert. Id. at 1316, 1319. Rather, that expert must provide verifiable evidence that the expert's testimony is based on "scientifically valid principles." Id. at 1318. Possible objective sources of such verification include learned treatises, the policy statement of a professional association, and published articles in reputable scientific journals. Id. at 1319.

2. Expert Testimony Based On Technical Or Other Specialized Knowledge

In Kumho Tire, the U.S. Supreme Court extended the holding of Daubert to expert testimony based on technical or other specialized knowledge, but did not give trial courts additional, specific indices of factors to be analyzed. Rather, the Supreme Court left trial courts to their own devices in fashioning standards for determining reliability and relevance, because Daubert standards simply may not apply. The test of reliability must be "flexible" and the trial judge may need to be creative in tailoring the test of reliability to the facts of a particular case. Kumho Tire, 119 S. Ct. at 1175.

The flexibility of trial judges in assessing the reliability of expert testimony is illustrated in the following product liability cases.

In Jaurequi v. Carter Manufacturing Company, Inc., 173 F.3d 1076 (1999), the Eighth Circuit dealt with the issue of the testimony of a mechanical engineer in a case involving defective farm machinery. In that case, the Court affirmed summary judgment, holding that the testimony of the mechanical engineer regarding the adequacy of a warning device was inadmissible. The engineer had not tried to construct an alternative device, nor had he tested its utility. Further, he had not shown any other manufacturer who had used an alternative device similar to that proposed by the expert. Thus, the Court held that the mechanical engineer's opinions were nothing more than "unabashed speculation." Furthermore, the expert's testimony on the failure to warn issue was not relevant, because warnings printed on the machinery by the manufacturer had been painted over at some point after the machinery left the hands of the manufacturer. In addition, plaintiff had been verbally warned of the dangers of the machinery. Thus, the Court held that any insufficiency in the painted-over warning signs was irrelevant to the issue of causation.

In Kent v. Howell Electric Motors, 1999 U.S. Dist. LEXIS 10940 (E.D. Penn., 7/20/99), applying Kumho Tire, the Court held that the testimony of an engineering expert is unreliable if the expert does not rule out obvious alternative causes for a product defect or failure.

C. Relevance

Relevance, in the context of expert testimony, involves a determination of whether there is a "fit" between the expert's testimony and a material issue in the case. Daubert I, 509 U.S. at 591-92. This "fit" analysis most often goes directly to the issue of causation and is the point at which trial judges may now have the discretion to move into areas more traditionally reserved for the jury.

For example, in Nemir v. Mitsubishi Motors Corp., 1999 U.S. Dist. LEXIS 12132 (E.D. Mich., 7/30/99), the issue before the Court was partial latching of a seat belt. The Court found plaintiff's expert's testimony to be neither reliable nor relevant. Plaintiff's expert had run a number of tests to show that it was it was possible to achieve partial latch of the seat belt. However, the trial court found that the expert's methods were not representative of how a person would actually use a seat belt; therefore, the expert's tests could not be tied to the facts of the case. Even though plaintiff had testified that he believed that he had fully engaged his seat belt, the trial court held that it was "sheer speculation" for plaintiff's expert to suggest that a driver could accidentally fail to insert the latch plate all the way into the buckle mechanism or to accidentally partially press the release button. Because plaintiff's expert had to carefully manipulate the buckle in order to achieve partial latching, the Court held that it "strain[ed] credulity" to suggest that partial latching could be achieved by inadvertence. Thus, the Court concluded that plaintiff's expert's deliberate testing methods were not relevant to the issue of whether partial latching can occur inadvertently or whether it did occur inadvertently in this case.

A New York court reached the opposite result in Guild v. General Motors Corp., 1999 U.S. Dist. LEXIS 9690 (W.D. N.Y. 6/1/99). Guild was also a seat belt case, but plaintiff claimed inertial unlatching. Like plaintiff in Nemir, Guild claimed she was belted but that the seat belt released on impact in an accident. Plaintiff's experts postulated that inertial unlatching had occurred; defendant's experts countered that initial unlatching does not happen in real world accidents. The trial court held that plaintiff's expert's testimony was admissible, stating: "the mere fact that a difference of opinion exists does not make plaintiff's expert's conclusions inherently unreliable." Any deficiencies in plaintiff's expert's theories would go to the weight of the evidence, not its admissibility.

II. Excluding Plaintiff's Experts

A. Procedure

Counsel should always investigate the credentials of the opposing party's experts. Daubert has not changed that. However, Daubert has re-emphasized the role of the trial judge as "gatekeeper" and the duty of the trial judge to carefully examine experts' reliability and the relevance of their testimony.

The party presenting an expert's testimony has the burden of showing that that testimony is both reliable and relevant. In accordance with Federal Rule of Evidence 104, the judge is to determine "preliminary questions" concerning an expert's qualifications and the "admissibility of evidence." Determination of the reliability or relevance of expert testimony may require a Daubert hearing. Trial judges are charged with gathering complete information and may look for assistance to a court-appointed expert. Standards and Procedures for Determining the Admissibility of Expert Evidence After Daubert, 157 F.R.D. 571, 580-85 (1994).

The importance of an adequate Daubert hearing is demonstrated in two cases. In Padillas v. Stork-Gamco, Inc., 1999 U.S. App. LEXIS 18013 (3rd Cir., 8/2/99), the trial judge granted defendant's motion for summary judgment because he found inadmissible the evidence of plaintiff's technical engineer, which was plaintiff's only evidence of liability in this product liability case. The trial court held that the expert's report did not meet the standards of Daubert because it provided no basis for the expert's conclusions and observations, did not show whether the expert had done research or had experience in machine design, did not include the expert's methodology or whether he had conducted any tests, and was filled with conclusory, unsupported statements. The Third Circuit reversed on the ground that, even though the trial court may have been correct in its decision, the failure to hold an in limine hearing deprived plaintiff of a sufficient opportunity to support his expert's opinion.

The Court reached a similar result in DiPetrillo v. Dow Chemical Company, 729 A.2d 677 (1999). In that case, one of Dow Chemical's many motions in limine was a motion for a preliminary hearing to challenge the bases of plaintiff's causation expert's testimony. The trial court denied that motion, and the Rhode Island Supreme Court affirmed, holding that the motion failed to provide the trial judge with sufficient notice and specificity that defendants were claiming that plaintiff's expert's testimony was unreliable because it utilized unvalidated, novel, and complex scientific theories. The Court noted that had the defendant brought a proper motion or renewed its motion at trial, it would have been an abuse of discretion for the trial court not to hold an evidentiary hearing on the matter.

B. Excluding or Limiting Testimony by Plaintiff's Experts

1. Physicians and Dentists

In food cases, the Daubert test may be effective to exclude or at least limit the testimony of plaintiffs' experts. For example, plaintiffs will typically list a treating physician as an expert. Investigation of the physician should routinely include a litigation search and a call to the state medical, dental or other professional licensing association to ascertain whether the witness has been disciplined.

Even if the physician is qualified, the physician's testimony may not be reliable. For example, where a doctor diagnoses food poisoning, but does no pathogen testing, that diagnosis may be challenged as unreliable on the basis that the physician did not follow proper scientific procedures to arrive at that diagnosis.

2. Vocational Experts

Occasionally, plaintiffs in cut hand or other food cases may claim lost wages or diminished ability to work. Plaintiff's vocational expert's testimony may be excluded as unreliable.

For example, in Hough-Scoma v. Wal-Mart Stores, Inc., 1999 U.S. Dist. LEXIS 7046 (W.D. NY), plaintiff alleged that a rolled-up carpet, standing on its end, fell and hit her on the back of the head. At trial, plaintiff's expert testified that she would have to retire early based on certain "work-life expectancy" tables, due to her injury. The jury awarded plaintiff over half a million dollars in future lost wages. In response to defendant's motion for a new trial, the Court ruled that there was insufficient evidence to support the award of future lost wages. plaintiff's vocational expert was not competent to render a medical assessment of the plaintiff's residual functional job capacity, however, the expert had done just that in part of his opinion. In addition, to the extent that the vocationalist relied on work-life expectancy tables, the Court found that these tables lacked reliability because the statistical validity of the tables had not been established, there was no evidence that the tables had been subject to peer review, and the record was insufficient to establish whether such tables were regularly relied upon by vocational experts.

2. Economists

Plaintiffs with serious personal injuries often hire economists to provide the jury with a value for hedonic damages (loss of the enjoyment of life). Some of their statistical models do not meet the requirements of Daubert. See cases collected in Kurncz v. Honda North America, Inc., 166 F.R.D. 376, 388-89 (W.D. Mich. 1996).

III. Qualifying Defense Witnesses As Experts

In the typical trial of a food case, the defendant's primary witness will be a production or quality control person. That witness can testify generally regarding operations, manufacturing procedures and safety/quality controls, even though the witness probably was not actually on the plant floor. It may be beneficial to qualify the witness as an expert in order to permit the witness to give opinions on such things as whether the company adhered to industry standards.

Witnesses may be qualified as experts on the basis of knowledge, education, skill, experience or training. Defense counsel will bring out all of these credentials in laying the foundation for the witness's testimony. Assuming the witness is qualified on the basis of training or field experience, the testimony itself may be subject to scrutiny. The witness must be prepared to testify regarding his/her knowledge of both internal procedure and industry standards.

If, for example, Plaintiff claims to have found a small piece of metal in his/her food and the metal is determined to be composed of aluminum, the well qualified production expert should be able to testify specifically about USDA standards for acceptable food processing equipment. His/her expertise will allow the witness to offer testimony regarding these standards and will eliminate the processing equipment as a potential source of the metal.

More recently, Hazard Analysis and Critical Control Points Principles (HACCP) programs are being required of many food manufacturers. The witness should be well versed in his/her particular HACCP program and the food safety process controls utilized in the plant. Expert testimony from the production witness concerning USDA and FDA requirements for HACCP programs can be quite effective as it is rare that the judge or jury fully understands or appreciates the lengths to which the food processor goes to ensure quality.

1. ⁰ The Frye test may retain its validity in jurisdictions, such as Michigan, where that standard is incorporated in the rule of evidence. Michigan Rule of Evidence 702 restricts expert testimony to that which is generally accepted in the scientific community because that rule only permits opinion testimony in the form of "recognized scientific, technical, or other specialized knowledge." (emphasis added).