Slip and fall cases with an allegedly dangerous Slips Trips and Falls caution signor defective surface frequently involve the surface’s coefficient of friction (COF) or “the degree of slip resistance.” The higher the COF, the less slippery the surface will be. Evidence concerning a surface’s COF is typically presented by expert witnesses. The expert will opine on the appropriate COF industry standard and on whether the surface in question meets that standard. This recent Eleventh Circuit case turned on the reliability of the Plaintiff’s expert’s opinions.

The Plaintiff slipped on the pool deck of the cruise ship, which was wet from rain. She fractured her wrist and sued for damages, alleging negligence. Plaintiff sought to present expert testimony on the COF of the pool deck and publications that stated COF standards applicable to cruise ship pool decks.

Plaintiff’s expert, who was a civil engineer, conducted COF testing on the deck. The expert performed his tests following a rainfall and produced a COF range from 0.70 to 0.14, with an average value for all his wet testing of 0.45. The expert also looked at a video of the Plaintiff’s accident and her deposition testimony. The expert opined that a COF of 0.45 was “below minimum standard values that have long been accepted as required in order to classify a walkway surface as slip-resistant.”

But in striking the expert’s testimony and the publications in support of the industry COF standard, the district court ruled that Plaintiff’s expert was qualified to testify as an expert with regard to the slip resistance of the pool deck of the cruise ship, as (1) individuals’ mental and physical reactions to surfaces with varying slip resistances; and (2) the necessity and adequacy of warnings concerning such surfaces. However, the court held that the expert’s opinions were not based on reliable methods.

The Plaintiff’s expert put forth a “false sense of security” theory. The district court held that his testimony was unreliable because he had not tested the COF of the deck along the path that the Plaintiff walked before she slipped. The district court also excluded the Plaintiff’s expert’s testimony as to the COF results obtained from the area where Plaintiff slipped because the tests were conducted nearly a year and a half after the accident. The district court believed that Plaintiff failed to show that the same conditions existed on the deck at the time she fell. Also, the ATSM standard that the expert cited in opining that 0.6 was the minimum acceptable COF for the deck was applicable only to crew members aboard ships, the district court said.

As a result, the district court granted summary judgment in favor of the Cruise Line. With the exclusion of the expert’s testimony and opinions, the court concluded that Plaintiff’s other evidence failed to create an issue of fact as to whether the cruise line created a dangerous condition on the deck because of improper maintenance.

Circuit Judge Aldaberto Jordan for the U.S. Court of Appeals, Eleventh Circuit, initially reviewed the publications the expert relied on for his opinion of the industry COF standard. Evidence of custom within a particular industry is admissible as bearing on the standard of care in determining negligence, the judge explained. “Compliance or noncompliance with such custom, though not conclusive on the issue of negligence, is one of the factors the trier of fact may consider in applying the standard of care.”

But Jordan held that the district court abused its discretion as to the ASTM section applied. The judge noted that on a cruise ship, both the crew and passengers walk over many areas, including the pool decks. Crew members, he wrote, come into contact with pool decks for “operation” and “maintenance,” as described in § 1.2. As a result, in such commonly traversed areas, the COF standard in § could apply. A deck constructed of a single material (like teakwood in this case) ca not be designed to meet two different COF standards for passengers and for crew at the same time.

The Plaintiff’s expert reported that the COF when he tested it in wet conditions was below what he contended to be the minimum acceptable COF for cruise-ship passenger decks, but he did not opine that the deck at the time of the accident was below the minimum acceptable COF. Jordan and the Eleventh Circuit held that the district court abused its discretion here by improperly applying the governing legal standard to the record before it.

Judge Jordan explained that the “substantial similarity” test, a test found in various evidentiary standards, generally governs when a party seeks to introduce an out-of-court experiment to recreate a critical event or incident. Here, any evidence on the similarity of the deck at the time of testing was contrary to the district court’s finding. Plaintiff’s expert and that of the Cruise Line testified that the deck’s wet condition when tested was substantially similar to its condition at the time of the accident. Also, a Cruise Line representative testified that the deck itself had not been changed since the Plaintiff’s accident. This testimony, the judge held, was sufficient evidence of “substantial similarity” to allow admission.

However, the district court did properly rule on the reliability of this test. The Plaintiff’s expert’s theory was essentially that, because the COF values in the area he tested (the area where Plaintiff slipped) ranged from 0.70 to 0.14, the same range of values could be expected across the entire deck surface. So, a person could walk across the deck without experiencing any instability, then suddenly, step on an area of the deck where the COF dropped significantly. And so, “presumably, one would feel secure until one is not secure.”

The district court correctly noted that there was a significant problem with the expert’s opinion as to his purported “false sense of security” theory. The expert did not perform any COF tests along the path Plaintiff traveled to determine if the COF values there varied to the same degree as the values obtained from the area he actually tested. Also, the viewing of the video of Plaintiff walking along the deck just before her fall did not give the expert the ability to opine on the COF measurements of the portions of the deck he failed to test. Moreover, Judge Jordan said that the expert could not cure the deficiency in his methodology by merely walking along the same path that the Plaintiff covered and saying that he did not feel he like he was going to slip!

The expert’s subjective physical and mental perceptions were not the sort of reliable methodology that Rule 702 requires. Consequently, the district court correctly ruled that his “false sense of security” theory was unreliable.

The Eleventh Circuit affirmed in part and reversed in part the district court’s evidentiary rulings, vacated the grant of summary judgment, and remanded the case.