EvidenceProf Blog

Editor: Colin Miller
Univ. of South Carolina School of Law

Friday, October 4, 2013

Ipse Dixit & The Admissibility of Expert Opinion Testimony

Federal Rule of Evidence 702 provides 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 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 has reliably applied the principles and methods to the facts of the case.

So, how is a federal judge to determine whether a witness is qualified to give expert opinion testimony at a trial? In its opinion in Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), the Supreme Court enumerated several factors the district court may use to assess the reliability of proffered scientific testimony, including:


(1) whether the theory or technique can be (and has been) tested, (2) whether the theory or technique has been subjected to peer review and publication, (3) in the case of a particular scientific technique, the known or potential rate of error, and (4) whether the theory or technique is generally accepted by the relevant scientific community.


So, where did that leave the plaintiffs in Cooper v. Marten Transport, Ltd., 2013 WL 5381152 (11th Cir. 2013)?

In Cooper

husband and wife Tom and Gail Cooper were involved in a low-speed car accident with a tractor trailer driven by Dwayne Stroman on behalf of Marten Transport, Ltd. After the collision, the Coopers sought treatment for back pain and ultimately underwent surgery. The Coopers filed an Amended Complaint against Stroman and Marten Transport, alleging causes of action for negligence and negligent retention and hiring.

After the district court deemed certain evidence inadmissible, including the proposed expert testimony of Dr. William C. Hutton, a biomechanical engineer, the Coopers appealed. Dr. Hutton 

would have explained that the 2010 collision caused damage to the Coopers' spines and lumbar discs. Specifically, Dr. Hutton would have opined that the combination of three stresses—the Coopers' obesity, the probable twisting of their spines to the left due to the fact that they were likely turned looking at oncoming traffic, and the flexion of their spines from being seated—“would have been enough to damage the disc[s] or exacerbate a pre-existing lumbar degenerative disc” when Stroman ran into them.

The district court, however, "excluded Dr. Hutton's testimony as unreliable, explaining that he spent only five hours reviewing case material, that a significant portion of that time was devoted to thinking, and that his methodology was to rely on his 40 years of experience." On appeal, the Coopers claimed that "the district court failed to account for Dr. Hutton's extensive experience and his many peer-reviewed publications wherein he articulated the principles underlying his opinion in this case."

The Eleventh Circuit disagreed, concluding that

The district court did not abuse its discretion in excluding Dr. Hutton's testimony. While “there are instances in which a district court may determine the reliability prong under Daubert based primarily upon an expert's experience and general knowledge in the field...at all times the district court must still determine the reliability of the opinion, not merely the qualifications of the expert who offers it.”...Although Dr. Hutton has extensive experience in his field, his opinion in this case was not the product of a scientifically reliable methodology. He generated his opinion that the 2010 collision caused the Coopers' back injuries, or aggravated preexisting problems, by learning and thinking about the Coopers' case and reaching a conclusion. Dr. Hutton specifically admitted that in arriving at his opinion he did not conduct any testing. Dr. Hutton's methodology was not reliable because it was not derived from the scientific method; rather, it amounted to asking the district court simply to “tak[e] the expert's word for it.”

Specifically, according to the court, "[a]s we have repeatedly cautioned, “nothing in either Daubert or the Federal Rules of Evidence requires a district court to admit opinion evidence that is connected to existing data only by the ipse dixit of the expert.” Ipse dixit is Latin for "he himself said it," meaning the only proof we have of the fact is that this person said it.



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"the district court must still determine the reliability of the opinion, not merely the qualifications of the expert who offers it."

I do not believe that Daubert stands for the proposition and I hope they ask for SCOTUS review. The TJ is not the gatekeeper of the opinions of the experts, he is the gatekeeper of the evidence. If the Court is the gatekeeper of the expert witness's opinion then the Duabert rule disappears in a cloud of dust. The court points out a lack of individualized testing but if one could do individualized testing one would never need an expert's opinion in the first place.

Posted by: Daniel | Oct 9, 2013 5:40:32 PM

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