ABSTRACT: The Eighth Circuit Court of Appeals, applying Federal Rule 702 and Daubert, affirmed the U.S. District Court’s exclusion of a medical causation expert’s testimony, which claimed to apply differential diagnosis, but did so in a faulty manner.

Plaintiff Lancaster brought suit in the United States District Court for the District of Nebraska claiming that her husband’s lung cancer was caused by his exposure to diesel exhaust, silica and asbestos during his 33-year career with BNSF Railway Company (“BNSF”). BNSF moved for summary judgment arguing that Plaintiff’s experts failed to base their opinions on sufficient and admissible evidence to establish causation. Plaintiff retained two experts, Dr. Zimmerman, a Ph.D. who provided an industrial hygiene opinion, and Dr. Chiodo, an M.D. who provided a “medical causation opinion.” 

Mr. Lancaster was a trackman and foreman from 1974 through 2007. He worked in the office a few hours a week as a section foreman, which had the potential to expose him to asbestos according to Zimmerman. Zimmerman was unable to quantitatively determine Mr. Lancaster’s exposures to diesel exhaust or asbestos due to the lack of air monitoring but based on the testimony regarding Lancaster’s work around silica dust from dumping and tamping of ballast stone, he concluded that Lancaster was exposed to silica in levels that exceeded safe levels and at times were dangerously high.

Dr. Chiodo’s opinion was predicated on Zimmerman’s exposure opinions. Unfortunately, Dr. Chiodo’s recitation of Zimmerman’s exposure opinions was inaccurate and flawed. Dr. Chiodo believed Zimmerman opined that “Lancaster was exposed to silica, asbestos and diesel exhaust above and beyond what the average person would be exposed.”

The Federal Employers’ Liability Act requires a plaintiff to plead and prove the common law elements of negligence. Typically, in order to establish the connection between the injury and alleged exposure, expert evidence is required. A medical expert’s proper role is not only to prove that the alleged exposure is capable of causing an injury, but that it caused the particular injury alleged by plaintiff.

Under the Federal Rules of Evidence, Rule 702 an expert’s testimony is admissible if (1) it is based on sufficient facts or data, (2) it is a product of reliable principles and methods and (3) the application of the principles and methods has been completed reliably. A court under Rule 702 may conclude that there is “simply too great an analytical gap between the data and the opinion proffered.”

Although BNSF argued that both Zimmerman’s and Chiodo’s opinions were insufficient under Rule 702, the District Court admitted Zimmerman’s opinion, concluding that it was based on reliable and sufficient data and that he accurately applied reliable methods to the facts.  As typical in a Rule 702 analysis, the trial court observed that any alleged deficiencies in an expert’s techniques would be addressed at trial through cross-examination, as these issues go towards weight and not admissibility. 

Dr. Chiodo’s opinion, however, was found to be deficient. According to Dr. Chiodo, Lancaster was exposed to cigarettes, asbestos, diesel combustion fumes and silica and anyone could have caused his cancer. Dr. Chiodo simply opined that Lancaster was exposed to all four carcinogens, in some unknown amount, and each could have caused his cancer. The District Court concluded that Dr. Chiodo’s opinion was connected to the data solely by the “ipse dixit” of the expert.

Although Dr. Chiodo claimed he performed a differential diagnosis analysis, he cited four separate potential causes, failed to support his determination with any evidence, and significantly, failed to rule out any of the potential causes of Mr. Lancaster’s lung cancer. He also failed to rule out Lancaster’s smoking as a non-occupational potential cause of his lung cancer, which the District Court pointed out undermined Dr. Chiodo’s differential etiology. The District Court therefore held that Dr. Chiodo’s opinions and testimony did not “bridge the gap between general and specific causation.”

The United States Court of Appeals for the Eighth Circuit agreed with District Court and affirmed its granting of summary judgment in BNSF’s favor. Specifically, the Eighth Circuit pointed out that there was no direct evidence that Lancaster was exposed to asbestos or diesel combustion fumes and more importantly there was no evidence of the level of exposure. Since there was no evidence for the factfinder to conclude that Lancaster was exposed to levels known to cause the injury claimed by him, Dr. Chiodo’s opinions were speculative. Dr. Chiodo’s opinions lacked sufficient foundation which directly impacted his methodology. The Eighth Circuit found that Dr. Chiodo was unable to support causation and that was enough by itself to grant summary judgment in favor of BNSF. Id.

Because Dr. Chiodo is an oft-utilized plaintiff expert in FELA toxic exposure cases, the Eighth Circuit’s decision may be beneficial to defendants seeking to exclude Dr. Chiodo’s opinions in the future.