Tolley v. ACF Industries, Inc
In Tolley v. ACF Industries, Inc., 212 W. Va. 548, 558, 575 S.E.2d 158, 168 (2002), the Court explained that "the law is clear that a mere possibility of causation is not sufficient to allow a reasonable jury to find causation."
Tolley was a deliberate intention action filed by an employee alleging that his preexisting asthma was aggravated by chemicals in his employer's paint department.
However, the employee's medical expert could not identify the actual cause of his respiratory condition. The expert was only able to opine that there were three potential causes for the employee's alleged aggravation of his pre-existing asthma.
The Court concluded that the employee's reliance on "indeterminate expert testimony on causation that [was] based solely on possibility" was insufficient. Id.