If More Than “Say So” Is Required, Will Human Factors Experts Ever Be Permitted To Testify In Delaware?

    If More Than “Say So” Is Required, Will Human Factors Experts Ever Be Permitted To Testify In Delaware?

    Human Factors Expert

    Court: Superior Court of Delaware, New Castle
    Jurisdiction: Federal
    Case Name: Ward v. Shoney’s, Inc.
    Citation: 847 A.2d 367


    The plaintiff was on her way to purchase a newspaper from a vending machine located outside a Shoney’s Restaurant. As she approached the entrance of the building, she walked through the landscaping to take a shortcut. As a result, the plaintiff tripped on the raised edging that separated the landscaping from the sidewalk. The plaintiff’s negligence case was paired down to two claims: (1) Shoney’s was negligent for failing to anticipate that pedestrians would “cut the corner” through its landscaping, and (2) Shoney’s negligently maintained a “raised edge”  along the border of the landscaping in a manner which created a tripping hazard for pedestrians who did “cut the corner.”

    In this case, the court was called upon again to fulfill its responsibility as gatekeeper to ensure that expert testimony proffered for presentation at trial was relevant and reliable. The expert testimony in question principally involved human factors engineering, loosely defined as “the study of how humans act and react in certain situations.”

    The Expert

    The plaintiff offered the testimony of a civil and structural engineer with experience in human factors engineering to support the position that Shoney’s, Inc. negligently designed the walkway and adjoining landscaping leading into its restaurant by failing to anticipate that the landscaping, in certain circumstances, could constitute a tripping hazard. Specifically, the expert testified that Shoney’s should have anticipated that patrons would intentionally depart from the walkway and enter the landscaping when rounding the corner of the restaurant. According to the expert, the raised edging separating the landscaping from the sidewalk was a dangerous condition of which Shoney’s should have been aware.

    Shoney’s moved in limine for an order excluding the expert’s testimony on the ground that it is not competent under D.R.E. 702.

    During his first discovery deposition, the expert opined that Shoney’s should have anticipated that pedestrians entering and leaving its restaurant would “cut the corner” through the landscaping. Based on this well-known propensity of human behavior, the expert opined that the raised edging which separated the walkway and the landscaped area constituted a dangerous condition of which Shoney’s should have been aware.

    When Is An Expert Qualified To Opine On Human Factors?

    The plaintiff’s expert acknowledged that he had received no special education or training in the field of human factors engineering. He did not consider himself to be a human factors engineer, as he was a licensed civil engineer. Yet he regularly confronted human factors issues in his work and suggested that they were integral to an engineer’s design work.

    With respect to the expert’s qualifications, the court was satisfied that he was competent to offer opinions in human factors engineering based on his extensive work experience designing structures with their intended and expected use in mind.

    However, the expert acknowledged that his methodology amounted to no more than drawing upon his practical knowledge. He did not refer to specific industry standards, studies, guidelines, regulations, scholarly works, or peer-reviewed information of any kind.  While it’s true that published works need not form the basis of the expert’s opinion, the absence of such foundation “was one factor in determining whether an expert’s opinion was based on good grounds.” Not only did the expert decline to cite objective information in support of his opinion, but he also declined to provide even anecdotal support. He mentioned nothing of other cases or incidents which support the contention that Shoney’s should have known that Ms. Ward would walk through its landscaping and trip over the edging. And, perhaps most importantly, the expert could point to nothing other than his “say so” to support the notion that the design of the walkway was flawed, or that the landscaping was a dangerous condition of which Shoney’s should have been aware.

    In the face of this record, the court could not abrogate its responsibility to act as gatekeeper and excluded testimony from the plaintiff’s expert. The lack of methodology employed by the expert was ultimately inadequate to permit his opinion to be presented to the jury.

    The court held that the civil and structural engineering expert’s opinions were not reliable and, therefore, not admissible.

    Final Thoughts

    The court returned to the concern that prompted this lengthy opinion: if more than the expert’s “say so” is required, will human factors experts ever be permitted to testify in a Delaware courtroom? From the judge’s perspective, the answer to this question was: “it depends….” If the opinion was based simply upon the ipse dixit of the expert, and that was all the human factors experts were able to muster in support of their opinions, they would find a gatekeeper unwilling to admit them into the courtroom.

    If, on the other hand, the human factors expert is able to demonstrate some reliable methodology at the heart of his opinion, the gate would be opened and the opinion would be admitted in evidence (subject, of course, to admissibility under other applicable rules of evidence). The court must be satisfied that process and methodology are not foreign to the human factors expert, even when he addresses the peculiarities of human behavior. Accordingly, the court must be confident that this opinion will not be misconstrued as a broad attack on the discipline of human factors engineering, or as a blanket exclusion of these experts from Delaware litigation.