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April 2010

Ninth Circuit Court of Appeals Provides Guidance on Application of Daubert Rule for Expert Opinion Testimony

Primiano v. Cook, 2010 DJDAR 6228 (9th Cir. April 27, 2010)

Amending an opinion previously filed March 10, 2010 and appearing at 598 F.3d 558 (9th Cir. 2010), the Ninth Circuit Court of Appeals, covering the Western United States including California and numerous other states where Gordon & Rees maintains offices, provided important guidance on the application of the so-called Daubert rule, which excludes from trial unqualified expert opinion testimony.  Originally a response to the increasing admission of what was popularly called "junk science," Daubert v. Merrell Dow Pharm., Inc., 509 U.S. 579 (1993),  decided by the U.S. Supreme Court in 1993 and codified in Federal Rule of Evidence 702, requires expert testimony to be based on "sufficient facts or data" and be the product of "reliable principles and methods."  The Court then followed in 1999 with Kumho Tire Co. v. Carmichael, 526 U.S. 137 (1999), which held that the Daubert framework applies not only to scientific testimony but to all expert testimony.

In the immediate case, the plaintiff and appellant, Marylou Primiano, went through five separate elbow surgeries to implant and then correct an artificial joint made by the defendant, Howmedica,  and which included polyethylene components to prevent metal components from rubbing up against each other.  It didn't work. Primiano sued Howmedica for products liability. Howmedica's experts opined that the device failed due to misalignment and complications related to Primiano's age and arthritis. The district court excluded the opinion of Primiano's medical expert--who had viewed x-rays but not actually seen the patient--that the device must have been defective because it wore out so quickly, as not meeting the Daubert standard, and granted Howmedica summary judgment. The district court reasoned that admissibility required that the opinion be based on "an objective source." 

The Ninth Circuit reversed. Under Daubert, expert opinion testimony must be relevant and reliable. Such testimony is relevant if the knowledge underlying it has a valid connection to the relevant inquiry. It is "reliable if the knowledge underlying it has a reliable basis in the knowledge and experience of the relevant discipline." However, medical expert testimony need not be conclusive because such knowledge is often uncertain. Further, the "test of reliability is 'flexible' and Daubert's list of specific factors neither necessarily nor exclusively applies to all experts or in every case," and the trial court has discretion in evaluating the reliability of expert testimony based on "the particular circumstances of the particular case."

Under Federal Rule of Evidence 702, to be admissible, (1) the evidence has to "assist the trier of fact" either "to understand the evidence" or "to determine a fact in issue"; (2) the witness has to be sufficiently qualified to render the opinion.  "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, if (1) the testimony is based upon sufficient facts or data, (2) the testimony is the product of reliable principles and methods, and (3) the witness has applied the principles and methods reliably to the facts of the case."  As the Supreme Court held in Daubert, FRE 702 replaced the old test of Frye v. United States, 293 F. 1013 (D.C. Cir. 1923), of "general acceptance in the particular field."

The Ninth Circuit noted, " [T]he requirement that the opinion testimony "assist the trier of fact" "goes primarily to relevance." For scientific opinion, the court must assess the reasoning or methodology, using as appropriate such criteria as testability, publication in peer reviewed literature, and general acceptance, but the inquiry is a flexible one. Shaky but admissible evidence is to be attacked by cross examination, contrary evidence, and attention to the burden of proof, not exclusion. In sum, the trial court must assure that the expert testimony "both rests on a reliable foundation and is relevant to the task at hand." 

Here, Primiano's expert had a sufficient basis in education and experience in the field, and sufficiently explained his opinion's connection to the relevant inquiry. Thus, it should have been admitted. That the expert never examined Primiano would go to impeachment, not admissibility of his opinion testimony.  The Court also noted that the lack of peer-reviewed scientific literature or other objective, evidentiary basis does not necessarily make expert opinion inadmissible, particularly in a field like medicine where much decision-making "relies on judgment--a process that is difficult to quantify or even to assess qualitatively.   Especially when a relevant experience base is unavailable, physicians must use their knowledge and experience as a basis for weighing known factors along with the inevitable uncertainties" to "mak[e] a sound judgment."  

The Court continued, "When considering the applicability of Daubert criteria to the particular case before the court, the inquiry must be flexible. Peer reviewed scientific literature may be unavailable because the issue may be too particular, new, or of insufficiently broad interest, to be in the literature. Lack of certainty is not, for a qualified expert, the same thing as guesswork. "Expert opinion testimony is relevant if the knowledge underlying it has a valid connection to the pertinent inquiry. And it is reliable if the knowledge underlying it has a reliable basis in the knowledge and experience of the relevant discipline." "[T]he factors identified in Daubert may or may not be pertinent in assessing reliability, depending on the nature of the issue, the expert's particular expertise, and the subject of his testimony." Reliable expert testimony need only be relevant, and need not establish every element that the plaintiff must prove, in order to be admissible.
The significance of this decision may lie in its apparent relaxation of strict requirements for outside objective support for an expert's proffered opinion in order to make it admissible.  Possibly this will be limited to fields such as medicine where, as the Court noted, judgment looms large, but it is hard to imagine any field in which such an argument cannot be made.  Be sure to look for citations of this case in future instances where the admissibility of expert opinion is contested.


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