Insights & Events

On this Strafford CLE-accredited webinar, Hollingsworth LLP partner Elyse Shimada and her co-panelists will consider strategic takeaways on the admissibility of general causation expert testimony under FRE 702 in products liability and mass tort litigation to be gleaned from the In re Acetaminophen ASD-ADHD Prods. Liab. Litig., 707 F. Supp. 3d 309 (S.D.N.Y. 2023) MDL. Speakers will analyze the district court’s 2023 order excluding all plaintiffs’ causation experts, the legal impact of President Trump’s and HHS Secretary Robert F. Kennedy, Jr.’s actions in response to these findings, the arguments the parties made to the Second Circuit Court of Appeals in November 2025, and, if available, its decision. Register now.

Plaintiffs have sued the maker of Tylenol, as well as retailers and marketers of store brand acetaminophen, alleging failure to warn, negligence, negligent misrepresentation by omission, breach of implied warranty, and design defect based on inadequate warnings that acetaminophen, when taken by pregnant mothers, can cause autism in their children. Legal commentators have suggested that “pregnancy-safe” marketing messaging by manufacturers, retailers, and pharmacy chains could trigger consumer protection and false advertising claims, and that employers and insurance companies could have claims for reimbursement and economic loss claims based on alleged concealment of risks and elevated long-term care costs. Plaintiffs must prove, with medical causation expert testimony that meets the FRE 702 standards, that acetaminophen can cause autism, not just that there might be an association between prenatal acetaminophen use and autism. This causation analysis applies regardless of the product or drug in question, and the Tylenol MDL is one of the most significant tests of amended Rule 702.

Panelists will discuss the district court judge’s holdings that all the experts in the Tylenol MDL failed under FRE 702 as a result of using mixed diagnoses, cherry-picking studies, accepting flaws in some studies but not others, and ignoring confounding factors. The case, and any decision on appeal, will be highly influential on what it means for a court to scrutinize whether an expert’s opinion reflects a reliable application of the principles and methods to the facts of the case.