Expert Witness Blog

Expert witness should conduct necessary tests and investigation, and not just rely on others or risk being excluded. In Mitchell v. Gencorp, Inc., 165 F.3d 778, 779 (10th Cir. 1999), the plaintiff contended he had developed leukemia from regularly working in an unventilated room where hazardous materials were stored. The court excluded the industrial hygienist expert, noting that the expert merely studied photographs of the room and material-safety data sheets listing the chemicals stored there. The expert “never visited the flammable room and conducted no air tests to demonstrate [the plaintiff’s] level of exposure to the chemicals. Moreover, he did not attempt to re-create the level of exposure through computer modeling.”