In Bostic, et. al. v. Georgia-Pacific Corporation, 57 Tex.Sup.Ct.J. 1091, the Supreme Court of Texas reaffirmed that the “substantial factor” causation test applies in asbestos personal injury cases, defined the quantitative evidence necessary to establish causation, and reversed a jury’s award of damages.
Plaintiffs Susan Bostic, Helen Donnahoe and Kyle Anthony Bostic alleged causes of action for negligence and product liability, alleging that exposure to Georgia-Pacific’s asbestos-containing drywall joint compound caused decedent Timothy Bostic’s mesothelioma and death. The decedent and his father mixed and sanded joint compound during remodeling products, and alleged they used Georgia-Pacific’s product 98 percent of the time. After finding liability under negligence and marketing defect theories, the jury assessed 75 percent of the causation to Georgia-Pacific, and 25 percent to a former employer of both the decedent and his father.
The court of appeals reversed the verdict, finding legally insufficient causation evidence. In appealing to the Supreme Court, the plaintiffs argued that the testimony of the decedent, the decedent’s father and experts supported the jury’s verdict that Georgia-Pacific products caused the decedent’s mesothelioma. In response, Georgia-Pacific contended that the expert testimony as to causation was inadmissible as speculative.
First, the Supreme Court rejected the plaintiffs’ argument that the causation standard of “any exposure” should apply to claims involving mesothelioma, as it ignores scientific fact and would function as absolute liability. More importantly, Georgia-Pacific convinced the court to use a quantitative approach to causation in asbestos cases. The court found instructive its decision in Merrell Dow Pharmaceuticals, Inc. v. Havner, 953 S.W.2d 706 (Tex. 1997), which involved claims of birth defects from a mother’s use of Benedictin. There, it held that establishing causation, absent direct evidence, requires expert testimony that the plaintiff’s exposures to a defendant’s product more than doubled the plaintiff’s risk of contracting the disease. Finding that this holding was grounded in the tort principle that only reliable scientific testimony can assist a trier of fact, the court held that the standard applies to substantial factor causation in asbestos cases.
Further, the court held that only epidemiological studies of exposures similar to those claimed by a plaintiff could support causation. Similarity can be shown by studies of individuals with the same exposure type, duration and levels, as well as latency of disease. Based thereon, the testimony of four of the plaintiffs’ causation experts were dismissed as unreliable, given their conflicting claims that a single fiber can be causative, while also conceding that mesothelioma is dose responsive. As no quantification of the decedent’s exposure to Georgia-Pacific’s products remained, the court of appeals’ judgment was affirmed.
Bostic will significantly alter the expert discovery tactics involved with claims of injuries resulting from asbestos exposure. The increased burden on plaintiffs to produce causation evidence will allow new means in which to discredit or disqualify the testimony of their experts. Further, claims involving injuries with limited scientific support for measurements of potential exposures may be reduced or eliminated, given their decreased likelihood of successfully showing causation.