The Mississippi Supreme Court earlier today upheld the reversal of a $2 million benzene verdict. In Watts v. Radiator Specialty Co., et al., No. 2006-CA-01128-SCT (Miss. June 12, 2008), the Court’s opinion focused on the absence of scientific evidence linking non-Hodgkin’s lymphoma, plaintiff’s condition, to benzene exposure.

Plaintiff alleged that his use of the product “Liquid Wrench” during his employment as a mechanic exposed him to benzene, and in turn caused his non-Hodgkin’s lymphoma. Plaintiff was diagnosed with small-cell lymphocytic lymphoma, a subtype of non-Hodgkin’s lymphoma in 1999. Liquid Wrench is a liquid solvent used for cleaning tools and engine parts and loosening nuts and bolts. Beginning in 1947, and throughout much of his career, Watts allegedly used Liquid Wrench as many as five times a day. It was undisputed that during at least 18 years of his usage Liquid Wrench did contain benzene.  In the 2004 trial, a jury found defendants Radiator Specialty and U.S. Steel liable.

In May 2006, however, the trial court granted the defendants’ motion for judgment notwithstanding the verdict after finding that the testimony of the plaintiff’s expert on the issue of causation should have been excluded as scientifically unreliable. Dr. Levy testified as to general causation (that benzene causes non-Hodgkin’s lymphoma) and specific causation (that benzene-containing Liquid Wrench caused Mr. Watts’s non-Hodgkin’s lymphoma). In particular, the trial court found that neither the cohort studies nor the case control studies relied upon by Dr. Levy at trial supported his opinion that a causal connection exists between benzene exposure and non-Hodgkin’s lymphoma. (Cohort studies identify and study a group of people exposed to a certain element as compared to another group not exposed to the element to see if there is a higher incidence of disease in the group exposed.; case-control studies identify and study a group of people who have a disease as compared to a group of people who do not have that disease to see if there is a higher incidence of exposure to a certain element in the group that has the disease.) The trial court entered an order dismissing the plaintiff’s case with prejudice, and the plaintiff appealed.

The State Supreme Court’s Analysis

The high court noted the defendants’ central contention that there is no evidence of a link between benzene exposure and small-cell lymphocytic lymphoma. The defendants claimed that Dr. Levy thus had insufficient support for his testimony that a demonstrable causal association exists between benzene exposure and non-Hodgkin’s lymphoma.

Mississippi follows the standard for expert testimony described in Daubert v. Merrell Dow Pharmaceuticals Inc., 509 U.S. 579 (1993). Trial judges are expected to assume the role of gatekeeper on questions of admissibility of expert testimony. There was no dispute that Dr. Levy was properly qualified as an expert in epidemiology and occupational medicine, but there was an issue regarding the reliability of his causation testimony.

The methodology used in forming his opinion as to general causation was the review of eighteen case studies done by different researchers between 1979 and 2004 (nine cohort studies and nine case-control studies). While this type of epidemiological study review is certainly an accepted methodology in the state, an analysis of these case studies supported the trial court’s finding that Dr. Levy’s testimony as to the content of the studies and their relevance to the facts of this case could easily have misled the jury. (The Court believed that juries are often in awe of expert witnesses and their impressive lists of honors, education and experience.)

Dr. Levy admitted that only half the studies showed a statistically significant increase in risk due to benzene exposure. None of the studies specifically looked at the possible risks associated with use of Liquid Wrench. None specifically studied the risks of development of non-Hodgkin’s lymphoma in mechanics, Watts’s profession. (The studied occupations included oil refinery workers, gas station attendants, general chemical workers, and seamen on tankers. ) One of the studies suggested that the reported increase in risk of non-Hodgkin’s lymphoma was not occupationally related. Several of the studies did not provide a dose-response ratio. In short, the Court believed, none of these studies provide a basis for the conclusion that there is a causal connection between benzene exposure and non-Hodgkin’s lymphoma, much less small-cell lymphocytic lymphoma, the particular type from which plaintiff suffered. The Court also emphasized the fact that the expert’s testimony gave very little detail, if any, as to the specific findings of each case study and why it might be relevant.

While experts need not rely on studies that explicitly support their testimony, it is significant that none of the studies relied upon by Dr. Levy found a conclusive link between benzene exposure and non-Hodgkin’s lymphoma.

Dissent Misses the Mark

Three justices in dissent disagreed with this conclusion, arguing that the trial court abused its discretion in excluding Dr. Levy’s testimony. Specifically, the dissent took issue with the emphasis on the conclusion that none of the studies found a link between benzene exposure and non-Hodgkin’s lymphoma. But the majority found it crucial that the few positive findings were not statistically significant, and/or did not relate to the relevant type of lymphoma, and/or that the higher risk of non-Hodgkin’s lymphoma was found among chemical workers who were exposed to a number of chemicals other than benzene and thus the observed risks could be due to some other exposure.

The Court drew upon the language of the United States Supreme Court in General Electric Co. v. Joiner, 522 U.S. 136 (1997), in which the Court observed that an expert’s conclusions and methodology are not entirely distinct from one another. Trained experts commonly extrapolate from existing data. But nothing in either Daubert or the Rules of Evidence requires a district court to admit opinion evidence which is connected to existing data only by the ipse dixit of the expert. A court may conclude that there is simply too great an analytical gap between the data and the opinion proffered.

The dissent also asserted that the majority’s decision would effectively resurrect the Frye standard requiring an expert’s opinion to be generally accepted in the scientific community. Frye v. United States, 54 App. D.C. 46, 47, 293 F. 1013, 1014 (1923). Quite to the contrary, this case is a good example of how courts should apply Daubert. Acceptance remains a relevant factor for trial courts to consider under Daubert. And the gap between the data and the conclusion was simply too great.