The Superior Court of Pennsylvania recently rejected the plaintiff's expert's opinion on causation, in an interesting Frye decision.  See Snizavich v. Rohm and Haas Co., No. 1383 EDA 2012, (Pa. Super. Ct. Dec. 6, 2013).

Plaintiff's decedent filed suit against Rohm and Haas in April 2009, asserting causes of action under the Wrongful Death and Survival Acts, in which she alleged that decedent’s brain cancer was caused by exposure to chemicals while working at Spring House, and that Rohm and Haas was allegedly liable.  Plaintiffs submitted an expert report, which defendant challenged in a Frye motion and then hearing.  The trial court rejected the expert opinion and then granted defendant summary judgment. Plaintiff appealed.

The trial court was especially troubled by the plaintiff's expert, Dr. Milby’s, reliance on a report from the University of Minnesota (“Minnesota Report”), finding an association between brain cancer and working at the Spring House, PA facility where thousands of chemicals had been used. The Minnesota Report was inconclusive as to both the cause of the brain cancer found in the Spring House workers and the relationship between the chemicals and increased incidence of brain cancer. Nevertheless, as the court stated, Dr. “Milby somehow comes to the exact opposite conclusion . . . Milby, however, does not state any scientific methodology that he used nor does he call into question the [study’s] methodology that might make its findings incorrect, rather he simply stated his own opposite conclusions without any further support.”  Ultimately, the Milby expert report seemed to be little more than an unscientific lay opinion given by someone who happened to be a medical doctor. As such, Dr. Milby’s testimony would not assist the trier of fact, because it contained no evidence, causal or otherwise, linking the decedent’s brain cancer to the Spring House facility.

Under Pennsylvania law, admissible expert testimony that reflects the application of expertise requires more than simply having an expert offer a lay opinion.  Testimony does not become scientific knowledge merely because it was proffered by a scientist.  Wack v. Farmland Industries, Inc., 744 A.2d 265, 271 (Pa. Super. 1999) abrogated on other grounds by Trach v. Fellin, 817 A.2d 1102 (Pa. Super. 2003). Likewise, expert testimony must be based on more than mere personal belief, Commonwealth v. Stringer, 678 A.2d 1200, 1202 (Pa. Super. 1999), and must be supported by reference to facts, testimony or empirical data.  Downey v. Crozer-Chester Medical Center, 817 A.2d 517, 528 (Pa. Super. 2003) (en banc).

The exercise of scientific expertise requires inclusion of scientific authority and application of the authority to the specific facts at hand. Thus, the minimal threshold that expert testimony must meet to qualify as an expert opinion rather than merely an opinion expressed by an expert, is this, observed the court: the proffered expert testimony must point to, rely on or cite some scientific authority – whether facts, empirical studies, or the expert’s own research – that the expert has applied to the facts at hand and which supports the expert’s ultimate conclusion. When an expert opinion fails to include such authority, the trial court has no choice but to conclude that the expert opinion reflects nothing more than mere personal belief.

Here, the appellate court agreed that Dr. Milby failed to demonstrate any scientific basis, other than his own subjective beliefs, that the chemicals used at Spring House caused brain cancer. He basically reviewed plaintiff's medical records, work history, and work conditions, and then relied on the Minnesota Report.  However, the Minnesota Report was inconclusive as to the cause of the brain cancer found in the Spring House workers and the relationship between the chemicals used at Spring House and brain cancer. Although Dr. Milby references and seems to rely on the Minnesota Report, he ignored the fact that it specifically and intentionally disclaims that exact conclusion that he himself reaches.  Dr. Milby did not offer any other scientific authority that even suggested a causal relationship between possible exposure to chemicals at Spring House and brain cancer, or any reason to doubt the scientific veracity of the Minnesota Report. The Milby expert opinion was, therefore, more aptly described as scrupulously avoiding the medical literature, and based entirely on subjective assessments of both cause and effect.

Thus, the Superior Court concluded that Dr. Milby’s opinion was nothing more than lay opinion offered by an expert and therefore was inadmissible. The decision reinforces the burden facing plaintiffs in toxic tort cases to proffer expert testimony with a sufficient scientific basis, especially where there are numerous idiopathic cases, where the scientific and medical literature has not found a conclusive causal link between a given product and the alleged injury.