Christophersen v. Allied-Signal Corp.

The issue presented by this appeal is how a court should determine the admissibility of expert opinion testimony. At the summary judgment stage of this ease, plaintiff attempted to establish medical causation of a toxic tort through the testimony of a single expert witness. The district court held that the basis of the expert’s opinion was insufficiently reliable and, in the alternative, that the expert’s testimony would have been more prejudicial than probative. With the expert’s testimony ruled inadmissible, plaintiff was left without proof of causation. The district court entered summary…