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Daubert Motions

What is a Daubert Motion

By Bert Certain

A Daubert motion is a specific type of motion in limine intended to exclude unqualified evidence from being presented to the jury. Specifically, Daubert motions concern the testimony of an expert witnesses who does not possess the requisite level of expertise, or which utilize questionable methods in data gathering. Daubert motions take their name from the 1993 Supreme Court case, Daubert v. Merrell Dow Pharmaceuticals. Rules 702 and 703 of the Federal Rules of Evidence govern the admission of scientific evidence in federal court. The rules allow expert witnesses greater leniency in their testimony because it is presumed that the expert will have a reliable basis in knowledge and expertise in his field. For this reason, the court in Daubert required that trial judges act as a gatekeeper and determine the scientific validity of scientific evidence before admitting it.

The decision in Daubert articulated a two-pronged test for admissibility of scientific expert witness testimony: (1) The testimony must be relevant. The relevancy of a testimony refers to whether or not the expert’s evidence aids the finder of fact (typically the jury or a judge) in deciding the facts of a case. (2) The scientific testimony must be reliable. The Supreme Court held that in order for expert testimony to be reliable, the expert must have derived his or her conclusions from the scientific method. The Court offered illustrative, but not exclusive, examples of factors in determining acceptable scientific method:

- Whether the data was gathered through empirical testing. The theory or technique must be falsifiable, refutable, and testable.

-Whether the findings were subjected to peer review and publication.

-The known or potential error rate and the existence and maintenance of standards concerning its operation.

-Whether the theory and technique is generally accepted by a relevant scientific community.

While these factors are not exhaustive, they are still standard guidelines that courts use today in determining the admissibility of expert testimony. Though the decision in Daubert was restricted to the evidentiary issues in that case, the ‘gatekeeper’ and ‘reliability’ guidelines in the decision have been expanded to include technical and specialized knowledge testimony as well.

Daubert Motions in United States v. W. R. Grace

In United States v. W. R. Grace, a Daubert hearing was held on January 21 and 22, 2009, and Judge Molloy’s order was filed on February 10th, 2009. The order addressed three distinct issues.

First, the court ruled that the expert testimony of Dr. Christopher Weis was admissible. Dr. Weis is a toxicologist working for the Environmental Protection Agency (EPA). Dr. Weis has indicated that he will testify that exposure to asbestos fibers at former W.R. Grace facilities and other locations throughout the Libby community constitute an ongoing risk to residents, due to the tendency of human activity to disturb dust or soil and cause heightened concentration of airborne fibers in the human breathing zone.

Judge Molloy ruled that the testimony of Dr. Richard Lemen, an epidemiologist and former acting director of the Notional Institute for Occupational Safety and Health (NIOSH), is admissible. Dr. Lemen has indicated in his Supplemental Expert Witness Disclosure that he will testify, “The vermiculite materials left by Grace in the town of Libby posed an imminent danger to the public from exposure to the materials, which could cause asbestos-related diseases such as asbestosis, lung cancer, or mesothelioma, and that endangerment persisted until the contamination was remediated.”

Regarding the testimony of Dr. Weis and Dr. Lemen, the order specifically excluded testimony that would rely on evidence of indoor or non-ambient releases of asbestos contaminated vermiculite, historical product testing, or soil sampling for the purpose of proving the asbestos fiber concentration levels required for a conviction of the charged Clean Air Act violations. Such testimony is still admissible to prove that defendants had knowledge of the dangerousness of asbestos contaminated vermiculite.

The Ninth Circuit previously held that the district court had erred in excluding expert testimony based on documents and studies derived from indoor air releases and expert testimony based on Grace’s historical product testing. The Court of Appeals found an abuse of judicial discretion and remanded these evidentiary issues to the District Court. On remand, Judge Molloy took the rather remarkable stance that the Court of Appeals misunderstood his previous Order. In his February 10, 2009 order, Judge Molloy maintained his previous ruling that indoor air studies are inadmissible if offered to demonstrate a release causing simultaneous endangerment or to prove the fiber concentration of a post-1999 ambient air release that would be required to beat the statute of limitations on a Clean Air Act violation.

Finally, the Court ruled on the admissibility of the Agency for Toxic Substances and Disease Registry (ATSDR) report of a medical screening program in Libby, Montana. The report is referred to in the Order as either The ATSDR Report or The Peipins Study. The report links exposure pathways in the Libby area to Pleural abnormalities. The ATSDR report was ruled inadmissible on the grounds that participants were not randomly selected, the study lacked a control group, and it failed to account for the duration and intensity of past exposures. Again, Molloy seems to disregard the Ninth Circuit Court of Appeals’ holding that the study is admissible under Federal Rule of Evidence 702. Judge Molloy circumvents their holding by finding the study to be inadmissible under Federal Rule of Evidence 703 because it is not the type of study reasonably relied upon by experts in the field. Because neither Dr. Weis nor Dr. Lemen indicated that they relied upon the ATSDR Report as a primary basis for their testimony, it’s admissibility did not render their testimony inadmissible.