CAN EXPERT WITNESSES EXPRESS OPINIONS IN COURT THAT ARE NOT BASED UPON PEER-REVIEWED ARTICLES WITH ACTUAL DATA?

The Appellate Court in Garner v. BNSF Railway Company (2024) Cal App. 5th (Fourth Dist., Div. 1) reversed the trial Court’s dismissal of plaintiff’s lawsuit alleging that his father’s death resulted from occupational exposure to toxic levels of diesel particulate matter (DPM), benzene, rock dust from railroad ballast, asbestos, fibers, and creosote during four decades as a trainman for his employer’s railroad.  The father had developed Non-Hodgkin’s Lymphoma, a blood cancer.  The son brought suit under the  Federal Employers’ Liability Act (FELA) for wrongful death and survival actions. The trial court judge, acting as an “evidentiary gatekeeper,” dismissed the action.

According to the Court of Appeal, the trial court judge improperly reasoned that because there were no epidemiologist and/or animal studies, the medical expert’s testimony should not go to the jury.

As the Court of Appeal pointed out, the trial judge may only act as a “gatekeeper” to exclude expert opinions, if such opinions  are not reliable, or not based upon generally accepted methodology in the particular field of expertise.  It would be a step too far, said the Court of Appeal, to exclude general causation opinions on the basis that too few studies in the field have been conducted because of new or “novel” toxic exposure, or where there are too few victims to spend the necessary money to conduct expensive studies.

The trial judge invaded the role of the jury as the finder of fact by excluding the testimony according to the Court of Appeal.  New toxic exposures are being frequently encountered.  Studies cannot keep up with new toxic exposures.  The medical expert could therefore properly offer expert opinions on medical causation.