Presented by the Environmental & Toxic Tort Practice Group

Legal Updates for Environmental Law - August 2018

New Jersey Supreme Court Adopts “Daubert” Standard For Expert Testimony

by Lila Wynne, Esq.

On August 1, 2018, the New Jersey Supreme Court held in In re: Accutane Litigation that the trial court properly excluded the plaintiffs’ experts’ testimony on grounds that their methodology would not be accepted by the larger scientific community. Moving forward, the ruling will have a tremendous impact on all defense litigation matters in New Jersey.

Accutane is a prescription medication developed by the defendants and approved by the FDA to treat recalcitrant nodular acne. Accutane’s alleged role as a cause of gastrointestinal disease ultimately resulted in a series of lawsuits against the defendants. In this case, the plaintiffs claimed that a causal connection existed between Accutane and Crohn’s disease, a chronic gastrointestinal illness.  Over 2,000 plaintiffs who alleged that they developed Crohn’s disease as a result of taking Accutane filed suit.

In the years since many of the earlier Accutane cases were decided, epidemiological studies were published, all of which concluded that Accutane is not causally associated with the development of Crohn’s disease. The defendants in this mass tort litigation filed a motion seeking a hearing on the specific association between Accutane and Crohn’s disease. The hearing focused on the epidemiological studies. The parties did not dispute that there is an acknowledged hierarchy of medical evidence and that, generally, epidemiological studies are preferred to unsystematic clinical observations. The court noted that researchers sometimes look to animal studies for determining a given agent’s toxicity in humans. When there is a substantial body of epidemiological evidence that addresses the causal issue, animal toxicology has much less probative value.

In this case, the plaintiffs produced Dr. Arthur Asher Kornbluth, a gastroenterologist, and Dr. David Madigan, a statistician. Kornbluth’s testimony had two themes: (1) explaining why he found the epidemiological studies unreliable and uninformative regarding causation; and (2) explaining his reliance on other forms of evidence, such as case reports, animal studies, causality assessment and his biological mechanism hypothesis. He stated that most of the studies that looked specifically for Crohn’s disease were fatally flawed because they did not account for its “prodrome”—the period between the onset of symptoms and diagnosis—and that some studies did not have enough patients and were “under powered.” Dr. Madigan focused on whether the epidemiological studies were appropriately designed to discover an association between Crohn’s disease and Accutane, if such an association did exist. He concluded that, after accounting for the prodrome, the epidemiological studies did not provide statistically reliable information.

The defendants produced Dr. Maria Oliva-Hemker, a gastroenterologist, and biostatistician, Dr. Steven Goodman. Dr. Oliva-Hemker’s testimony focused on disputing Dr. Kornbluth’s testimony and explained why epidemiological studies are preferred to case reports and animal studies in the hierarchy of evidence. She explained that the cause of Crohn’s disease is unknown; that any theory regarding a biological mechanism was therefore unreliable; and that scientists would not ignore the available epidemiological evidence in favor of a hypothesis about a biological mechanism that has not been submitted for peer review. She added that the study on which the plaintiffs’ experts relied for their determination of the prodrome was very small and not representative of the average prodromal. She also explained why Dr. Kornbluth’s reliance on animal studies was flawed, namely, because dogs cannot get inflammatory bowel disease. Dr. Goodman’s testimony focused on why the epidemiologic evidence is the best available evidence on the question of Accutane’s causal relation to Crohn’s disease and why a meta-analysis was a proper way of pulling those study results to reach a conclusion that Accutane does not cause Crohn’s disease. His testimony explained why he and others in the scientific community would not regard the epidemiological studies to be invalid due to a prodrome issue.

After the hearing, the trial court excluded the plaintiffs’ experts’ testimony. The court regarded the standard established in Rubanick v. Witco Chemical Corp., 125 N.J. 421 (1991), as requiring an expert opinion to be based on a “sound, adequately-sounded scientific methodology involving data of the type reasonably relied on by experts in the scientific field.” The trial court found the plaintiffs’ experts’ testimony lacking and determined that their examination of the evidence was a “conclusion-driven attempt to cherry-pick evidence supportive of their opinion, while dismissing better forms of evidence that did not support their opinion.”

The Appellate Division reversed. While noting the trial court’s opportunity to view the witnesses first hand, the panel expressed that the trial court’s negative reaction to the plaintiffs’ experts was not supported by the record. The Appellate panel further noted that, although a trial court’s decision to admit or exclude evidence is subject to an abuse of discretion standard, a reviewing court owes “somewhat less deference” to determinations regarding expert testimony.

The court granted certification in this matter to address whether the trial court properly excluded the plaintiffs’ experts’ testimony; whether the Appellate Division employed the correct standard in reviewing that decision; and whether New Jersey’s standard for assessing the reliability of expert witnesses is in need of clarification. With regard to the last issue, the court considered whether the factors set forth in Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), would further elucidate New Jersey’s standard for the admissibility of expert testimony.

The New Jersey Supreme Court noted that there is little distinction between Daubert’s principles regarding expert testimony and New Jersey’s, and that Daubert’s factors for assessing the reliability of expert testimony will aid New Jersey trial courts in their role as the gatekeeper of scientific expert testimony in civil cases. Accordingly, the court reconciled the standard under N.J.R.E. 702 and relatedly N.J.R.E. 703 with the federal Daubert standard to incorporate its factors for civil cases. According to the court, analysis of the record led to a clear result: the trial court properly excluded the plaintiffs’ experts’ testimony. Moreover, the court reaffirmed that the abuse of discretion standard must be applied by an Appellate Court assessing whether a trial court has properly admitted or excluded expert scientific testimony in a civil case. In this matter, the trial court did not abuse its discretion in its evidential ruling; therefore, the Appellate Division erred in reversing the trial court’s exclusion of the plaintiffs’ experts’ testimony.

The New Jersey Supreme Court provided a comprehensive analysis of New Jersey Rules of Evidence 702 and 703, which control the admission of expert testimony. The court noted that in State v. Kelly, 97 N.J. 178, 223 (1984), the court identified three prerequisites to a determination that expert testimony is permissible:

(1) The intended testimony must concern a subject matter that is beyond the ken of the average juror; (2) The field testified to must be at a state-of-the-art such that an expert’s testimony could be sufficiently reliable; and (3) The witness must have sufficient expertise to offer the intended testimony.

The Kelly criteria elucidated application of the then-applicable “general acceptance” standard for admitting scientific evidence. For many years, the majority of state and federal jurisdictions, including New Jersey, adhered to the “general acceptance” standard first put forth in Frye v. United States, 293 F.1013 (D.C. Cr. 1923). Then, in 1991, the New Jersey Supreme Court moved away from rigid adherence to the general acceptance standard.

Rubanick marked the broadening of that standard. The Rubanick court instructed courts to “consider whether others in the field used similar methodologies.” The court explained that the proper inquiry was whether comparable “experts in the field would actually rely on that information.” In Landrigan v. Celotex Corp., 127 N.J., 404, 417 (1992), the court elaborated:

When relying on epidemiological studies, the Trial Court should review them and “then determine whether the expert’s opinion is derived from a sound and well-founded methodology that is supported by some expert consensus in the appropriate field.”

Moreover, Landrigan suggested tools for trial courts to use in rendering gatekeeping determinations about the reliability of an expert’s methodology when the ultimate scientific opinion is not itself general accepted, including “reference to professional journals, texts, conferences, symposia, or judicial opinions accepting the methodology.” Thus, methodology may be assessed for soundness using some of the same tools as general acceptance identifies for outcome.

Not long after those dual holdings, the Supreme Court issued its seminal Daubert opinion, pronouncing that Frye had been superseded by the adoption of the Federal Rules of Evidence, 509 U.S. at 585-87, and fashioning a new standard that “entails a preliminary assessment of whether the reasoning or methodology underlying the testimony is scientifically valid and … can be applied to the facts at issue.” The Court noted that “many factors will bear on the inquiry,” which became known as the Daubert factors.

The Court described the trial court’s task as a “flexible” inquiry into the scientific principles at issue, one whose “overarching subject is the scientific validity—and thus the evidentiary relevance and reliability—of the principles that underlie a proposed submission.” As in Rubanick and Landrigan, the Daubert court underscored that the trial court must focus on the expert’s principles and methodology—not on the conclusions they generate. The Supreme Court elaborated on its Daubert standard with two cases which, combined, round out the Daubert trilogy: General Electric Co. v. Joiner, 522 U.S. 136 (1997) and Kumho Tire Co. v. Carmichael, 526 U.S. 137 (1999). Federal Rule of Evidence 702 was amended in 2000 to reflect the Supreme Court’s trilogy of cases outlining the Daubert standard. A majority of states have adopted some form of the Daubert standard, either explicitly or implicitly.

After the Daubert trilogy, the court revisited the topic of the trial court’s gatekeeping role under N.J.R.E. 702. In Kemp ex rel. Wright v. State, 174 N.J. 412 (2002), the court held that the Rubanick standard should apply whenever “a medical cause-effect relationship has not been confirmed by the scientific community but compelling evidence nevertheless suggests that such a relationship exists.” The court explained that, by requiring a pretrial R. 104 evidentiary hearing, the trial court would be able to properly “assess whether the expert’s opinion is based on scientifically sound reasoning or unsubstantiated personal beliefs couched in scientific terminology. The Kemp court observed that New Jersey had not amended N.J.R.E. 702 to include “the three-factor test for the admissibility of expert testimony that is a part of the Federal rule as amended in response to Daubert.” Nor has any such action been taken since.

When the court modified the general acceptance standard to adopt a more relaxed approach for causation expert testimony in toxic tort litigation, and later for all medical cause-effect expert testimony, it envisioned the trial court’s function as that of a gatekeeper—deciding what is reliable enough to be admitted and what is to be excluded. Those are not credibility determinations that are the province of the jury but, rather, legal determinations about the reliability of the expert’s methodology. The court reinforces the rigor expected of the trial court in that role under existing New Jersey case law.

Here, the Appellate Division panel stated that, although a trial court’s decision to admit or exclude evidence is subject to an abusive discretion standard, a reviewing court owes “somewhat less deference to a trial court’s determination” regarding expert testimony. As support for that proposition, the panel relied on a criminal case that applied the Frye standard. The Supreme Court reaffirmed that the abuse of discretion standard applies in the appellate review of a trial court’s determination to admit or deny scientific expert testimony on the basis of unreliability in civil matters.

The Supreme Court next detailed the assessments made by the trial court in reaching its decision to exclude the testimony of the plaintiffs’ experts in this case. Both Drs. Madigan and Kornbluth employed a methodology whereby they disregarded eight of nine epidemiological studies and relied on case reports and animal studies. Despite their expressed conclusions regarding study-power, which is based in part on the size of the study at issue, and their rejections of the epidemiological studies, the plaintiffs’ experts were willing to ignore any such concern when relying on other studies to form an opinion as to the median prodromal period. The many contradictions in the experts’ methodology were not lost on the trial court, which concluded that experts in the scientific community would not accept as consistent with scientific norms a methodology such as that used by the plaintiffs’ experts. Moreover, Dr. Kornbluth never submitted his ideas concerning biological mechanism or Accutane’s relation to Crohn’s disease for peer review or publication. In sum, the trial court explained its reasons for concluding that the plaintiffs’ experts deviated from core scientific principles and strayed from their own claimed methodology in order to reach their conclusions. Under the abuse of discretion standard and the principles of Rubanick, Landrigan and Kemp, the New Jersey Supreme Court found that the trial court’s determination was unassailable. Therefore, they reversed the Appellate Division judgment.

With respect to the gatekeeping role, the New Jersey Supreme Court emphasized that it expects the trial court to assess both the methodology used by the expert to arrive at an opinion and the underlying data used in the formation of the opinion. The court noted: “There is not much light between New Jersey’s standard and that which has developed in the federal sphere under Daubert’s initial instruction.” Importantly, Daubert identified a non-exhaustive list of factors for courts to consider using if helpful. The court stated:

Distilled, the general factors identified as perhaps pertinent for consideration, but not dispositive or exhaustive, are: (1) whether the scientific theory can be, or at any time has been, tested; (2) whether the scientific theory has been subjected to peer review and publication, noting that publication is one form of peer review but is not a “sine qua non”; (3) whether there is any known or potential rate of error and whether there exists any standard for maintaining or controlling the technique’s operation; and (4) whether there does exist a general acceptance in the scientific community about the scientific theory.

The court noted that the last consideration—general acceptance in the scientific community—continues to have a bearing. The court, therefore, adopted the use of the Daubert factors but stopped short of declaring New Jersey a “Daubert jurisdiction” for two reasons. First, to date New Jersey retains the general acceptance test for reliability in criminal matters. Second, while the factors are helpful, and while individual cases may be persuasive in appropriate settings, there are discordant views about the gatekeeping role among Daubert jurisdictions. The Supreme Court’s view of proper gatekeeping and the methodology-based approach for reliability for expert scientific testimony requires the proponent to demonstrate that the expert applies his or her scientifically-recognized methodology in the way that others in the field practice the methodology. That approach was employed by the trial court.

The complete opinion may be found here:


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