The Court of Appeals for the Seventh Circuit reversed the exclusion of an expert’s testimony as unreliable. In Schultz v. Akso Nobel Paints, LLC, 721 F.3d 426 (7th Cir. 2013). The plaintiff’s decedent was a painter who used the defendant’s products between 1981 and 1989. He was diagnosed with leukemia in 2005 and died in 2006.
The district court excluded the expert’s opinion and granted defendant’s motion for summary judgment. That court had concluded that the expert’s testimony was unreliable because he merely testified that benzene is both generally known to cause leukemia and, specifically, was a substantial factor in the development of the decedent’s disease. The Court of Appeals held that the district court had seized on a portion of the expert’s testimony in which he discussed the “no threshold” idea and, on that basis, found the entirety of his opinion to be scientifically unreliable because the “no threshold” theory is “merely a hypothesis.” In addition, the district court also faulted the expert for failing to rule out other potential causes for the leukemia, particularly the history of smoking.
The Court of Appeals pointed out that under the applicable law, plaintiff was not required to demonstrate that benzene exposure was the sole cause of the disease so long as plaintiff showed that benzene either contributed substantially to the development of the disease or significantly increased the defendant’s risk of developing leukemia. The Court said that the evidence showed that this was done.