Gatekeeping is sometimes intellectually challenging, but the challenge does not excuse sloppy thinking. Understandably, judges will sometimes misunderstand the relevant science. The process, however, allows the public and the scientific community to see what is happening in court cases, rather than allowing the critical scientific reasoning to be hidden in the black box of jury determinations. This transparency can and should invite criticism, commentary, corrections, and consensus, when possible.
Bad legal reasoning is much harder to excuse. The Supreme Court, in Matrixx Initiatives, Inc. v. Siracusano, 131 S. Ct. 1309 (2011), unanimously affirmed the reversal of a trial court’s Rule 12(b)(6) dismissal of a securities fraud class action. The corporate defendant objected that the plaintiffs failed to plead statistical significance in alleging causation between Zicam and the loss of the sense of smell. The Supreme Court, however, made clear that causation was not required to make out a claim of securities fraud. It was, and would be, sufficient for the company’s product to have raised sufficient regulatory concerns, which in turn would bring regulatory scrutiny and action that would affect the product’s marketability.
The Supreme Court could have disposed of the essential issue in a two page per curiam opinion. Instead the Court issued an opinion signed by Justice Sotomayor, who waxed carelessly about causation and statistical significance, which discussion was not necessary to the holding. Not only was Justice Sotomayor’s discussion obiter dicta, but the dicta were demonstrably incorrect. Matrixx Unloaded (Mar. 29, 2011).
The errant dicta in Siracusano has already led one MDL court astray:
“While the defendant repeatedly harps on the importance of statistically significant data, the United States Supreme Court recently stated that ‘[a] lack of statistically significant data does not mean that medical experts have no reliable basis for inferring a causal link between a drug and adverse events …. medical experts rely on other evidence to establish an inference of causation.’ Matrixx Initiatives, Inc. v. Siracsano, 131 S.Ct. 1309, 1319 (2011).”
Memorandum Opinion and Order at 22, In re Chantix (Varenicline) Products Liability Litigation, MDL No. 2092, Case 2:09-cv-02039-IPJ Document 642 (N.D. Ala. Aug. 21, 2012)[hereafter cited as Chantix]. See Open Admissions for Expert Witnesses in Chantix Litigation.
It was only a matter of time before the Supreme Court’s dictum would be put to this predictably erroneous interpretation. See “The Matrixx Oversold” (April 4, 2011). Within two weeks, the error in Chantix propagated itself in another MDL case, with another trial court succumbing to the misleading dicta in Justice Sotomayor’s opinion. See Memorandum in Support of Separate Pretrial Order No. 8933, Cheek v. Wyeth Pharm. Inc. (E.D.Pa. Aug. 30, 2012)(Bartle, J.).
In Cheek, Judge Harvey Bartle rejected a Rule 702 challenge to plaintiffs’ expert witness’s opinion. I confess that I do not know enough about the expert witness’s opinion or the challenge to assess Judge Bartle’s conclusion. Judge Bartle, however, invoked the Matrixx decision for the dubious proposition that:
“Daubert does not require that an expert opinion regarding causation be based on statistical evidence in order to be reliable. Matrixx Initiatives, Inc. v. Siracusano, 131 S. Ct. 1309, 1319 (2011). In fact, many courts have recognized that medical professionals often base their opinions on data other than statistical evidence from controlled clinical trials or epidemiological studies. Id. at 1320.”
Cheek at 16. The Cheek decision is a welter of non-sequiturs. The fact that in some instances statistical evidence is not necessary is hardly a warrant to excuse the lack of statistical evidence in every case. The truly disturbing gaps in reasoning, however, are not scientific, but legal. Siracusano was not a “Daubert” opinion; and Siracusano does not, and cannot, support the refusal to inquire whether statistical evidence was necessary in a causation opinion, in main part because causation was not at issue in Siracusano.