Human Factors Expert Not Allowed to Opine on the Safety of the Flooring

On May 9, 2019, Plaintiff was injured while trying on a pair of capri pants in a Walmart dressing room. She was standing on one leg and putting her full weight on that leg when she fell. Plaintiff "fell down" and "ended up on her behind." Her "legs were towards the wall" with the hook (i.e., the right wall) and her body was positioned in "an L-shape." She fell "so fast that she was already on the floor before she realized what happened" and did not have time to break the fall with her hands.

Plaintiff retained Levi Dixon to opine on the "safety of the flooring used by Walmart in the dressing rooms of the at-issue store." Defendant sought to exclude Dixon's report because "his opinions and conclusions lack foundation and/or are not based on reliable methodologies."

Human Factors Expert Witness

Levi Dixon has a B.S. in Technology-Manufacturing Option and a M.S. in Human Factors & Ergonomics. Dixon has 13 years of experience in Safety and Risk Management. He has been involved in investigating and analyzing over 1,000 legal cases. Dixon is also a Certified Human Factors Professional, a Certified Safety Professional, and a Certified Tribometrist.

Want to know more about the challenges Levi Dixon has faced? Get the full details with our Challenge Study report.

Discussion by the Court

1. Dixon lacks specialized knowledge

Defendant first argued that Dixon's testimony should be excluded because Dixon lacks specialized knowledge.

Defendant asserted that Dixon "did not measure available slip resistance under the conditions at issue, did not analyze the traction demands of the specific posture of Plaintiff (i.e., standing on one leg while donning pants), and did not quantify any reduction from the textile at issue (i.e., linen) when interposed on the flooring at issue."

Plaintiff responded that (1) the industry standard of requiring a 0.50 coefficient of friction for a surface to be deemed safe for pedestrians "should be applied to the Walmart dressing room as patrons must ambulate in and out of the room"; (2) Dixon's "research, previous testing, and previous studies" permit him to "competently opine that the coefficient of friction in the Walmart dressing room fell well below the industry standard for safety"; and (3) "Dixon's explanation of what actions are to be reasonably expected in a dressing room is based on his safety analysis of user behavior inside of a dressing room and is consistent with everyday experience in dressing rooms" so "literature and studies are unnecessary to support basic safety analysis of foreseeable and expected behavior in a dressing room."

Plaintiff's argument relies on the Court accepting that the 0.50 friction/slip resistance coefficient benchmark for a pedestrian horizontal walking surface is the proper benchmark for flooring in a dressing room because an individual must walk into the dressing room. But Plaintiff, and others who use dressing rooms, are not walking while trying on clothing in a dressing room. Plaintiff concedes trying on pants in a dressing room "requires less friction to maintain stability" than the friction needed for walking. Accordingly, Dixon's citations to the benchmark that a friction/slip resistance coefficient of 0.50 is generally required for pedestrian horizontal walking surfaces is of little value in this matter. Dixon did not identify any safety principle identifying a benchmark for a safe coefficient of friction/slip resistance for flooring surfaces used in a dressing room. Because Plaintiff did not identify any guideline for a safe friction/slip coefficient in the context of dressing oneself in a dressing room beyond implicitly recognizing that a coefficient below 0.50 would be appropriate because less friction is required than for walking, the Court cannot conclude that Dixon has specialized knowledge in this field.

2. Dixon did not apply reliable methodology to sufficiently reliable facts

Defendant argued that Dixon's testimony should be excluded because it lacked sufficient facts or data, and his methods are unreliable.

Defendant concluded, "Dixon has merely inferred how the fabric-floor interaction 'created a slippery and unsafe condition' and caused or contributed to the fall—classic conclusory assertions unsupported by testing or validated modeling."

Dixon relied on studies evaluating the friction/slip resistance coefficient of terrycloth, cotton, and cotton blend textiles. Dixon did not opine on the friction/slip resistance coefficient of linen or how it would compare to terrycloth, cotton, or cotton blend. Dixon also did not opine on whether the friction/slip resistance coefficient of a pant leg and a sock or bathmat would be different. Instead, rather than providing testimony on how one would identify the friction/slip resistance coefficient in this case (a linen pant on vinyl floor while dressing oneself), Plaintiff argued that the fact Plaintiff fell while doing the comparatively safer activity of dressing oneself, "is evidence of how extremely low the coefficient of friction was with the introduction of textile on the hard flooring surface because undisputably Plaintiff's foot slipped." But it does not follow that the coefficient of friction was low simply because Plaintiff fell.

Dixon asserted that he could not do an analysis of the friction/slip resistance coefficient in this circumstance because the specific dressing room floor was not available. However, neither Dixon nor Plaintiff explain why Dixon's analysis is entirely absent of any analysis of a safe friction/slip resistance coefficient for an individual dressing oneself or the expected friction/slip resistance coefficient of an individual like Plaintiff who had linen pants stuck between her and a vinyl floor. As identified by Defendant, "how would Walmart even begin to argue that Dixon is wrong regarding a coefficient of friction value he has not derived, concerning a floor he has not identified, on premises he has not inspected?"

Accordingly, because Dixon did not identify (1) a benchmark for a safe friction/slip resistance coefficient for individuals dressing themselves nor (2) the expected friction/slip resistance coefficient for an individual in Plaintiff's situation, the Court cannot conclude that Dixon's "scientific, technical, or other specialized knowledge will help the trier of fact to understand the evidence or to determine a fact in issue."

Held

The Court granted Defendant's motion to exclude the testimony of Levi Dixon.

Key Takeaway

The Court is not tasked with deciding whether the expert is right or wrong, just whether the testimony has substance such that it would be helpful to a jury. The party seeking to introduce expert testimony evidence must show by a preponderance of the evidence that the testimony is admissible under Rule 702.

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