Louisiana Supreme Court Clarifies Daubert
In Freeman v. Fon’s Pest Management, Inc., the Louisiana Supreme Court found that the lower courts erred in granting the defendant’s motions in limine and striking the expert testimony of four of the plaintiff’s experts. The lawsuit alleged that the defendant used a pesticide which contained a chemical called fipronil to treat plaintiffs’ home for termites. Following the treatment, plaintiffs began to suffer headaches, nausea, dizziness, and confusion. To prove causation, plaintiffs retained four different experts – three toxicologists and one Certified Industrial Hygienist. In response, the defendant pest management company filed pre-trial motions to exclude the testimony of plaintiffs’ experts, claiming their testimony did not meet the standard for admissibility under Louisiana Code of Evidence article 702 and Daubert v. Merrell Dow Pharmaceuticals, Inc.
The district court granted the defendant’s motions in limine, striking plaintiff’s experts because it found: 1) none of the proposed experts had expertise regarding fipronil; 2) none of the four experts had written or contributed to any peer-reviewed articles regarding the effects of fipronil (or any pesticides) in humans; 3) none of the four experts attempted a dose reconstruction to determine the amount of exposure to fipronil allegedly suffered by the plaintiffs; 4) none of the experts reviewed any biological or air quality data to establish the plaintiffs were exposed to fipronil; and 5) no articles or studies reviewed by the experts proved any causal connection between fipronil and the plaintiff’s claimed injuries. In addition, the testimony of all four experts conflicted on the effects of fipronil exposure.
The court of appeal affirmed.
In its review of the lower courts’ rulings, the Supreme Court looked to the standard for determining the admissibility of expert testimony laid out in Daubert and codified in Louisiana Code of Evidence article 702 as follows:
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: (1) [t]he 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; (2) [t]he testimony is based on sufficient facts or data; (3) [t]he testimony is the product of reliable principles and methods; and (4) [t]he expert has reliably applied the principles and methods to the facts of the case.
In its opinion, the Supreme Court explained that “Daubert primarily concerns the methodology employed by the experts, ” and found that the trial court erred by focusing on the experts’ conclusions, rather than their methodologies. At the Daubert hearing, the defendants presented no contradictory evidence to show the plaintiff’s experts’ methodology to be improper for the formulation of their opinions on causation. Further, the district court incorrectly focused on the fact that none of the four experts wrote peer-reviewed articles regarding fipronil. Daubert does not require that an expert write any such articles in order for their opinions to be admissible, so long as their methodology has been subject to peer review or publication.
Next, the Supreme Court noted that Daubert does not require an expert to provide a “quantitative assessment to prove causation,” and the lower court “failed to recognize the plaintiffs could meet their burden of proving causation through either a quantitative or a qualitative assessment of fipronil exposure.” In this case, the experts performed a qualitative assessment and determined that exposure to fipronil caused the plaintiffs injuries.
Finally, the Court held that any conflicts among the experts’ testimony should be considered as a credibility determination, which did not affect whether the experts’ opinions were admissible or not.
Ultimately, the Louisiana Supreme Court reversed the lower courts’ findings and held that the district court abused its discretion in granting the defendants’ motions in limine with respect to the four experts in question. This decision by the Court provides insight into the relevant Daubert considerations and reaffirms that a party’s expert can use either a qualitative or quantitative methodology to meet the burden of proving causation, as both are acceptable under Daubert.