Schenk Scores Court of Appeals Victory in Case Involving Expert Testimony

Webb ruling clearly declares as “off limits” expert testimony on how fault should be divided among multiple parties

On September 5, 2007, the Arizona Court of Appeals ruled in favor of an Aiken Schenk client in Webb v. Omni Block, Inc.

Of interest to many attorneys is that the ruling makes clear that an expert witness is not permitted to advise the jury on how to determine the percentage of fault.

The decision stems from a lawsuit in which Joe Schenk represented the plaintiffs, Dr. and Mrs. Webb, in their efforts to recover damages against the defendant, Omni Block. At trial, an expert witness for Omni Block testified as to the specific percentage of fault (or lack thereof) for various parties and non-parties. Over the plaintiffs’ objection, the trial court allowed this testimony.

The Webbs appealed, challenging the appropriateness of the expert’s testimony regarding the percentage of fault. Under Rule 704, an expert witness is allowed to give an opinion on the “ultimate issue” in the case. However, in finding for the Webbs, the Court explained that:

“opinion testimony on an ultimate issue must still be helpful to the trier of fact and cannot be couched in legal conclusions that simply opine ‘how juries should decide cases.’ … We therefore hold that [Omni’s expert’s] opinion … constituted inadmissible legal conclusions under Rule 704 because he thereby told the jury how to decide the case.”

The Court’s opinion in Webb represents a first-time ruling that explicitly precludes an expert from expressing an opinion on the degree of fault or blame that should be assessed. In a number of cases, courts have ruled that an expert cannot tell the jury that a defendant was at fault, but none of those cases clearly declared as “off limits” expert testimony on how the fault should be divided among multiple parties. ●