Improper exclusion of expert testimony leads to reversal on appeal


Expert witness testimony plays a pivotal role in trial litigation. While the exclusion of an expert can be a fatal blow to the retaining party, an improper exclusion may lead to reversal of the decision on appeal. The 9th Circuit recently reversed the district court’s grant of summary judgment on the ground that the district court erred in excluding the testimony of the Plaintiff’s expert. The expert in question was Dr. Arthur Hoffman, the plaintiff’s car seat expert and the case was Lindner v. Ford Motor Co.


The lawsuit was brought by Matthew Lindner and Joseph Benson against Evenflo Company after the Linders were injured in a vehicle rollover accident in Mexico. During the accident, baby Camila Lindner was ejected from the vehicle and killed while strapped into an Evenflo car seat.  Lindler alleged that the carrier detached from its base due to a design defect as the latching mechanism provided no countermeasures to prevent the release handle from being actuated during the subject rollover. Dr. Hoffman was retained as an expert witness to testify that the carrier release handle was vulnerable to unintended unlatching during the dynamics of a rollover.

The United States District Court for the District of Nevada found the expert opinions to be inadmissible and granted summary judgment to Evenflo. In doing so, the court relied on the deposition of Dr. Hoffman and noted that he opined numerous times that the cause of the separation of the carrier from its convenience base was the release handle striking the front seat (or the front seat striking the release handle). However, the Court clarified that his own deposition testimony established that the basis of his opinion was an untested assumption.

Since Dr. Hoffman’s testimony was material to the case and the other experts had also deferred to his opinion, the Court granted summary judgment to the Defendants.

The Appeal

After almost two years and eight months, the 9th Circuit found the exclusion of Dr. Hoffman’s testimony to be an error and reversed.

The Court held that Dr. Hoffman had in fact, relied on empirical evidence,

“the release handle of that [child car] seat” was “exposed to the passenger front seat,” and the “passenger front seat. . . .was also deformed and slightly inclined.”

and this was not insufficient to support his opinion on causation.

The Court reversed the exclusion and also noted that the testimony of the experts would be sufficient to create a triable issue of fact in the case.