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February 23, 2016

New York Court Of Appeals Rejects "Reverse Engineering" Method Of Reaching Expert Opinion On Causation In Toxic Tort Case

Expert witnesses testifying in New York courts must demonstrate that their conclusions were reached using methods that have been "found to be generally accepted as reliable in the scientific community." Parker v Mobil Oil Corp., 7 NY3d 434 (2006), citing Frye v United States, 293 F. 1013 (D.C. Cir. 1923). In Sean R. v. BMW of North America, LLC, et al., 2016 NY Slip Op 01000 (Feb. 11, 2016), the Court of Appeals analyzed the methods by which plaintiff's expert reached the conclusion that the infant plaintiff was exposed to sufficient levels of toxins to have caused his injuries, and found those methods wanting.

In the spring of 1991, the infant plaintiff's mother began to notice a gasoline smell while driving the BMW 521i sedan purchased two years earlier. She continued driving the car throughout her pregnancy. Her son was born in 1992 with numerous birth defects, including spastic quadriparesis (a form of cerebral palsy), developmental delays, ventricular asymmetry, delayed myelination, microcephaly, aortic stenosis, malformed bicuspid valve, tracheomalacia and impaired visual function.

Two years after Sean was born, BMW issued a recall of all 521i sedans due to defects in the feed fuel hoses. This lawsuit followed in 2008, alleging that Sean's exposure in utero to the toxins contained in the gasoline fumes caused his birth defects.

Both defendants unsuccessfully moved for summary judgment on the grounds that the opinions of plaintiff's experts lacked a proper foundation. Defendants then moved to preclude plaintiff's causation experts from offering testimony at trial or, alternatively, to hold a hearing in accordance with Frye. In support, defendants provided affidavits from two of their own experts challenging plaintiff's experts' opinions as "novel" and not based on generally accepted scientific principles and methodologies. Supreme Court, New York County, granted the defendants' motion and the Appellate Division unanimously affirmed. On February 11, 2016, the Court of Appeals affirmed the lowers courts' decisions.

Under Parker, an expert opinion on causation in toxic tort cases must set forth: (1) a plaintiff's exposure to a toxin, (2) the toxin is capable of causing the particular injuries plaintiff suffered [i.e. general causation] and (3) that plaintiff was exposed to sufficient levels of the toxin to cause such injuries [specific causation]. In Sean R. v. BMW, plaintiff's experts pointed to scientific studies which established that exposure to the toxins in gasoline fumes in amounts of 1,000 parts per million could cause nausea, dizziness, headaches and throat irritation. One of the plaintiff's causation experts opined that, since the plaintiff's mother had complained of such symptoms, she must have been exposed to toxins in amounts of at least 1,000 ppm. Based on this analysis, plaintiff's second expert opined that the mother's exposure had caused the infant plaintiff's birth defects.

The Court of Appeals, however, rejected the experts' reasoning. The court accepted, arguendo, that the scientific literature established that exposure to gasoline fumes at levels of 1,000 ppm could cause the symptoms reported by plaintiff's mother. There was no evidence, however, that the described symptoms could not be caused by exposures significantly less than 1,000 ppm, and the studies used by plaintiff's expert did not support the conclusion that the presence of such symptoms necessarily implied the presence of toxins in that amount. Finding that "plaintiff and his experts have not identified any text, scholarly article or scientific study, "¦ that approves of or applies this type of methodology, let alone a 'consensus' as to its reliability," the court precluded the experts' testimony.

This case demonstrates that the Court will heavily scrutinize opinions of experts used to establish a connection between plaintiffs' injuries in toxic exposure cases, even going so far as to research and analyze medical and scientific theories. The decision also provides guidance regarding the level of reliability an expert must meet to satisfy the Frye test (i.e. to demonstrate that theories are scientifically accepted and therefore admissible). According to Sean R. v. BMW, plaintiffs will be obliged to show both a general association between an alleged exposure and the injuries suffered as well as quantify the level of exposure through methods that have been set forth within, and accepted by, the scientific community as a whole.

If you require further information regarding the content of this Legal Alert, please contact either of the Co-Chairs of the Torts & Products Liability Defense Practice Area, Thomas J. Drury, at (716) 858-3845 or, or Matthew J. Larkin, at (315) 425-2805 or,  or the Chair of the Mass & Toxic Torts Practice Area, Carol G. Snider at (716) 858-3782 or


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