Multidistrict litigation is meant to “promote the just and efficient conduct” of actions “involving one or more common questions of fact” by transferring those actions to a single district court “for coordinated or consolidated pretrial proceedings.” 28 U.S.C. § 1407(a). In MDLs involving alleged physical injury or illness caused by a product, one “common question of fact” is general causation. Each plaintiff in the MDL must prove that the product is capable of causing the injury or illness. We think it is usually — if not always — most “just and efficient” to address general causation on an MDL-wide basis as early as practicable. Some courts disagree, testing general causation initially on just a subset of plaintiffs in the MDL; when those efforts fail, other plaintiffs may be permitted to try again, perhaps with new general causation experts. But the plaintiffs’ second attempt to establish general causation often fails to remedy the problems that doomed the first attempt (as we have discussed before), merely amplifying costs for both parties before reaching the same result. The In re Deepwater Horizon BELO (Back-End Litigation Option) Cases litigation, while not formally centralized as an MDL itself, provides another example. In re Deepwater Horizon BELO Cases, 119 F.4th 937 (11th Cir. 2024).
Subject: Causation
Fifth Circuit Asks the Right Questions, Affirms Summary Judgment on Plaintiffs’ Herbicide Claims as Untimely and Lacking Admissible Expert Support for Causation
As Nobel laureate Richard Feynman once observed, “[w]isdom is knowing when to ask the right questions.” A related proposition is that wise jurists know how to identify and focus on the right questions. Motion practice can turn not only on the facts and the law, but on how the court frames the question to be answered. It is rarely a good sign for a party when the court articulates the issue differently than the party framed it. A recent decision by the Fifth Circuit provides not one, but two prime examples of how correctly framing the inquiry can dictate the results of a motion.
In Whalen v. Monsanto Company, 2024 WL 4524170 (5th Cir. Oct. 18, 2024), the plaintiffs alleged that the decedent had developed squamous cell carcinoma as a result of exposure to the defendant’s herbicide. The decedent was a doctor who had treated employees at a plant where the herbicide’s active ingredient was manufactured and was also an avid gardener who regularly used the herbicide. Initially, the plaintiffs alleged that the herbicide’s active ingredient was itself carcinogenic. However, they ultimately argued instead that the herbicide contained arsenic, which they claimed had caused the decedent’s cancer. The defendant moved for summary judgment, first as to selected claims on a statute of limitations argument, and later as to the remaining claims on the ground that the plaintiffs’ sole causation expert had not offered an admissible opinion, and the trial court granted both motions.
In re Taxotere (Docetaxel) MDL Court Rejects Plaintiffs’ Argument that Lone Pine Order is Unfair
We think Lone Pine orders are pretty fair. Lone Pine orders are case management orders that require plaintiffs in multidistrict litigation (MDL) to produce specific evidence without which the plaintiffs cannot make a prima facie case. There is nothing unfair about dismissing a case that is fatally flawed for want of critical evidence that cannot be obtained. Yet Lone Pine orders rarely sit well with plaintiffs who cannot (or do not want to have to) make the showing required of them. Rather than accept their fate, these plaintiffs often attack the Lone Pine order in an effort to delay the inevitable. We discussed one such effort in the In re Zostavax MDL in 2022 and earlier this year. The In re Taxotere (Docetaxel) MDL now provides another example, not only of how plaintiffs attack Lone Pine orders but also of how courts should respond to these unmerited attacks. In re Taxotere (Docetaxel) Prods. Liab. Litig., 2024 WL 4362982 (E.D. La. Oct. 1, 2024).
Third Circuit Affirms Lone Pine Order and Ensuing Dismissals in In re Zostavax MDL
In March 2022, the In re Zostavax MDL court entered a Lone Pine order requiring plaintiffs who claimed to have developed shingles as a result of using the Zostavax vaccine to produce certain test results supporting causation. In December 2022, the court dismissed 1,189 cases for failure to comply with that Lone Pine order. We posted about the Lone Pine order in April 2022 and the dismissal order in December of the same year. Now, on appeal, the Third Circuit has affirmed both the Lone Pine order and the dismissal. In re: Zostavax (Zoster Vaccine Live) Prods. Liab. Litig., 2024 WL 3423709 (3d Cir. July 16, 2024).
Zostavax is a vaccine meant to prevent shingles, a viral infection caused by the varicella-zoster virus (VZV). The vaccine introduces a weakened strain of VZV, triggering an immune response that primes the recipient’s immune system against non-vaccine sources of VZV (i.e., “wild-type strains”). VZV is responsible for both shingles and chickenpox, and it remains in the body for life. As a result, everyone who had chickenpox as a child faces a risk of the virus reactivating and causing shingles in adulthood. A laboratory test (called a “PCR test”) can reliably distinguish between the strain of VZV used in Zostavax and the wild-type strain one would find due to chickenpox infection.
Plaintiffs’ Second Bite at the General Causation Apple Fares No Better Than the First in Acetaminophen MDL
In December 2023, back when the ink was still drying on the amendments to Federal Rule of Evidence 702, the Southern District of New York excluded all five general causation experts proffered by plaintiffs in the In re Acetaminophen MDL whose cases had been selected for trial. We discussed that impressively detailed and painstaking decision here. Observing that all 50 states require proof of general causation in product liability cases and that the plaintiffs now had no experts to carry that water, the court instituted an order to show cause process that led to the dismissal of approximately 550 cases. However, over the defendants’ objections, the court permitted a small handful of new arrivals to the MDL to name their own general causation expert and try again. In yet another impressively meticulous opinion, the court recently doubled down on its Rule 702 “gatekeeping” role and excluded the new plaintiffs’ backup general causation expert in In re Acetaminophen – ASD-ADHD Prod. Liab. Litig., No. 22MC3043 (DLC), 2024 WL 3357608 (S.D.N.Y. July 10, 2024).
The plaintiffs in In re Acetaminophen allege that prenatal use of acetaminophen caused attention deficit hyperactivity disorder (ADHD) and/or autism spectrum disorder (ASD) in offspring. The plaintiffs’ first five proffered general causation experts were excluded in part because the court took issue with the experts’ “transdiagnostic” approach — combining literature of ADHD and ASD into a single analysis — because it merely “obscured limitations in the scientific literature.” The new plaintiffs’ expert — number six overall — sidestepped the “transdiagnostic” issues and sought to opine solely on a supposed link between prenatal acetaminophen use and ADHD. But the court, still mindful of acetaminophen’s critical role as the only pain reliever and fever reducer indicated for use during pregnancy and the FDA’s multiple reviews of its safety, remained vigilant in its Rule 702 obligation.
California Supreme Court Walks Middle Ground on Warnings Causation but Reaffirms Learned Intermediary Doctrine in Himes
As we reported in April, the United States Court of Appeals for the Ninth Circuit certified a question on California’s Learned Intermediary Doctrine in Himes v. Somatics, LLC, 2022 WL 989469 (9th Cir. Apr. 1, 2022). The California Supreme Court has now decided the issue in a way that walks the middle ground. On the one hand, the court rejected plaintiff’s call for recognizing an exception to the learned intermediary rule and reaffirmed the basic rule that a manufacturer’s duty to warn runs to the prescribing physician. On the other hand, the court ultimately lowered plaintiff’s burden of providing warnings causation. The opinion has clear ramifications not only on dispositive motion and trial practice, but on discovery strategies in prescription drug and medical device cases.
The question before the court was whether a plaintiff is “required to show that a stronger risk warning would have altered the physician’s decision to prescribe the product,” or whether a plaintiff may instead establish causation “by showing that the physician would have communicated the stronger risk warning[ ] to the plaintiff, either in their patient consent disclosures or otherwise, and a prudent person in the patient’s position would have declined the treatment after receiving the stronger risk warning.” (Himes v. Somatics, LLC, 16 Cal.5th 209 (2024).)

 
 