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Tenth Circuit Affirms Exclusion of “Human Factors” Expert

By Anthony R. McClure, Litigation News Associate Editor – January 20, 2011

In a cautionary tale for attorneys representing plaintiffs in products liability cases, the U.S. Court of Appeals for the Tenth Circuit recently held that a “human factors” expert’s testimony was properly excluded and, as a result, affirmed summary judgment in favor of an automobile manufacturer on a design defect claim. Graves v. Mazda Motor Corp.[PDF]. The Tenth Circuit held that the evidence presented by the expert “rests on no more than his say so—and that isn’t good enough to require its admission.”

The primary plaintiff, Cheryl Graves, rented a Mazda6 with an automatic transmission while visiting Mississippi. When Mrs. Graves pulled into the driveway of a private home to ask for directions, she thought she had put the car in park, but the car was actually in reverse. After she exited the vehicle, she was allegedly injured when the car door hit her and knocked her down. Mrs. Graves and her husband sued Mazda in the U.S. District Court for the Western District of Oklahoma. They claimed that the gear shift was defectively designed.

District Court Grants Summary Judgment
The plaintiffs retained a human factors engineer as an expert in support of their claims. According to one decision analyzed by the Tenth Circuit in its decision, “[a] human factors analysis focuses on the interaction between human behavior and the design of a machine or product.” The plaintiffs’ expert testified that the Mazda gear shifter’s design does not allow for “smooth” shifting and, as a result, is defective and unreasonably dangerous.

Applying the standard for allowing an expert to testify under Rule 702 of the Federal Rules of Evidence, as well as U.S. Supreme Court precedent in Daubert and Kumho Tire,the district court excluded the expert’s testimony as unreliable. After finding no other evidence in support of the plaintiffs’ design defect claim, the district court granted summary judgment in favor of Mazda.

Tenth Circuit Affirms
The Tenth Circuit agreed with the district court. It held that the expert’s testimony was properly excluded because the expert “failed to provide any data or industry standard, or to conduct any testing, to confirm his view that Mazda’s gear shift design was defective.”

The court noted that the expert failed to identify how smoothly a gear shift would normally move, how a defective gear shift might cause “shifting troubles for ordinary drivers,” or how this gear shift failed to comply with engineering standards. The court emphasized that no matter how well qualified an expert may be, a district court is not required to admit opinion evidence resting solely on the “say so” of the expert.

The plaintiffs cited two cases from outside the Tenth Circuit to argue that testimony from “human factor engineers” should be permitted without requiring further evidence. The court distinguished one case because it lacked sufficient analysis and used the other case to show that other human factor engineers usually do, in fact, rely on industry standards and methods. Because the plaintiffs’ expert testimony was deemed unreliable, and because there was no other evidence to support the plaintiffs’ claim, the Tenth Circuit affirmed summary judgment in favor of Mazda.

Nathaniel Cade Jr., Milwaukee, cochair of the ABA Section of Litigation’s Products Liability Committee, believes the Tenth Circuit decided correctly. “I did not think this was that difficult a case,” because, “the plaintiffs’ lawyer relied solely on one expert who, in fact, did no testing whatsoever,” he says.

Andrew S. Pollis, Cleveland, cochair of the Section of Litigation’s Consumer and Civil Rights Litigation Committee, believes the decision raises “an interesting overarching question which is the extent to which the Daubert and Kumho Tire decisions should have a role to play in summary judgment,” especially when a court decides these issues without a hearing. In other cases in which admissibility of an expert’s opinion is the lynch pin to the district court’s decision on summary judgment, Pollis has observed that district court judges may “defer the summary judgment decision and consolidate it with the Daubert hearing that would inevitably happen before trial anyway.” “To me, that is a more appropriate way to apply Daubert,” he says.

In Graves, the district court did not conduct a full Daubert hearing before excluding the expert and granting summary judgment. It observed that, although plaintiffs had conditionally requested a hearing, they also stated that they had “no additional briefing arguments or exhibits they would offer during any gatekeeper hearing pertaining” to the expert. Therefore, the district court did not believe such a hearing was warranted.

Possible Lessons
Commentators have advice for attorneys hoping to have this type of expert testimony admitted into evidence. Pollis says that, among other things, attorneys offering such evidence should “make sure you know what foundation a district court might require of you before an expert can render an opinion about a defective product.” Further, he says, “make sure that your expert has the necessary information based on either his or her own training and experience or based on information you can supply to the expert.”

Cade says that, in addition to analyzing the gearbox, he would have investigated whether there were scientific or industry studies on the issue. He cautions that the plaintiffs should not have only stated “why Mazda does it wrong without saying what is right, what is required by the industry, or what is standard.”

Keywords: litigation, expert witnesses, human factors expert

Related Resources

  • » Graves v. Mazda Motor Corp., No. 10-6011, 10-6094, 2010 U.S. App. LEXIS 25562 (10th Cir. Dec. 15, 2010).
  • » Graves v. Mazda Motor Corp., No. 08-0035, 2009 U.S. Dist. LEXIS 122414 (W.D. Okla. Dec. 17, 2009).
  • » Michaels v. Mr. Heater, Inc., 411 F. Supp. 2d. 992 (W.D. Wis. 2006).
  • » Kumho Tire Co., Ltd. v. Carmichael, 526 U.S. 137 (1999).
  • » Daubert v. Merrell Dow Pharm., Inc., 509 U.S. 579 (1993).


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