A recent decision from the Second Circuit provides an excellent reminder to practitioners to remember the fundamentals of expert selection and presentation. Certification of 1,300 cases as a part of multi-district litigation involving the same implantable medical device did not obviate the need for a well-developed theory of general causation that relies on expert witness opinion evidence to link the injury at issue with the product.
In the In Re Mirena IUD Products Liability Litigation, the Second Circuit affirmed a district court’s dismissal of a multi-district litigation after it held that the district court properly excluded expert witness opinion evidence on general causation (whether the type of injury at issue can be caused by the product). In Re Mirena IUD Products Liability Litigation, 2017 WL 4785947 (2d Cir. October 24, 2017). Plaintiffs-appellants were women who brought suit against Bayer HealthCare Pharmaceuticals Inc. for injuries when the intrauterine device (IUD) Mirena allegedly perforated, became embedded in, and/or migrated from their uteruses. Plaintiffs sued the manufacturer of the IUD, Bayer, alleging negligence, strict liability, manufacturing defect, design defect, failure to warn, breach of warranty (implied and express), negligent misrepresentation, fraud, and various state statutory violations. In 2013, nearly 1,300 cases were certified as part of the multi-district litigation.
While the court noted that “[b]oth parties agree—and Bayer has always warned—that Mirena can injure a woman’s uterus during insertion and afterward migrate outside the uterus (“primary perforation”),” the parties “disagree[d] about whether, in the absence of an injury at the time of insertion, Mirena® can later perforate and migrate from a uterus (‘secondary perforation’). Bayer did not warn about the possibility of post-insertion, secondary perforation, and thus is exposed to liability if secondary perforation in fact occurred.”
The Second Circuit upheld the district court’s exclusion of the plaintiff’s experts, finding that none of their tests had known error rates, were subject to peer review or were generally accepted in the scientific community. The tests had been developed for the purpose of litigation and most were not easily replicable. Further, the plaintiffs’ experts’ opinions all assumed the existence of the very fact in dispute and then worked backwards to hypothesize a mechanism by which it might occur.
Back to Basics: Considerations of an Expert’s Specialized Knowledge
Relying on Daubert v. Merrell Dow Pharm., Inc., 509 U.S. 579 (1993), the Second Circuit applied the highly deferential abuse of discretion standard in upholding the district court’s exclusion of the plaintiffs’ expert witnesses, focusing on three particularly noteworthy Daubert problems:
Degree of acceptance within the relevant scientific community. The theories proffered by the plaintiffs’ experts were not accepted in the wider obstetrics and gynecological scientific community. Not only did the experts fail to identify any authorities that directly support the existence of secondary perforation, but the scientific authority presented casted doubt on the phenomenon’s existence.
Pre-litigation expertise and development of theories for litigation. The experts lacked pre-litigation expertise in the phenomenon of secondary perforation and developed their theories for the purposes of litigation. Specifically, the Second Circuit noted that the plaintiffs’ experts had no specialized expertise in Mirena or uterine perforation before the Mirena litigation. Another proposed expert had no previous experience with IUDs or hormonal contraception. And yet another expert had not even heard of secondary perforation before consulting in the litigation.
Lack of direct support in literature and no prior research. Finding no direct support in the literature for secondary perforation and having conducted no prior research on the subject, the experts assumed the existence of the very phenomenon in dispute and then hypothesized how it could occur.
After upholding the district court’s exclusion of the plaintiffs’ experts, the court rejected the plaintiffs’ argument that putative party admissions were sufficient to establish general causation. The Second Circuit, in upholding the dismissal, noted the fact that all 50 states typically require expert testimony to prove causation where the causal relationship is outside the common knowledge of lay jurors.
Substantive Considerations for Selecting a Drug Product Liability Expert
Considering the above, prudent practice demands that general causation in drug or medical product liability cases be established through reliable expert witness opinion evidence linking the type of injury at issue to the product. It is equally critical to select proper experts at the inception of a case to establish general causation. The defense against such claims requires scrutiny of plaintiffs’ expert witness opinions and careful selection of defense experts to identify and refute unsubstantiated claims.
Substantive considerations include:
Technical credentials. A degree in a relevant subject at a nationally accredited university, licensing by state boards and membership in professional societies, including participation in continuing education requirements.
Relevant pre-litigation experience. A work history that includes employment at a university, government entity, corporation or technical institution in the relevant subject prior to the development of litigation theories. While specialized expertise with the product itself and the mechanism of injury is preferable, expertise with similar types of products, the subject injury or similar types of injuries may be useful.
Methodology. An expert’s background in testing, analysis, measurement and survey of technical, scientific or medical literature. Methodology developed in anticipation of litigation may be viewed as less credible. While an expert should also know the limits of his or her expertise, multiple experts may be retained to account for potential shortcomings. Previous testimony and the ability to communicate the methodology is equally significant.
Publications and studies. In the selection of expert witnesses to support a theory of causation, it is necessary for experts to have contributed to, or be well-versed in, the existing body of literature within the relevant scientific community.