Testimony Excluded After Expert is Unable to Rule Out Other Theories

    A federal appellate court in Iowa recently upheld a plaintiff expert witness’s exclusion in a workplace product liability case for their failure to satisfy the requirements of Federal Rules of Evidence 702. The decision in Hirchak v. W.W. Grainger, Inc., No. 19-2642 (8th Cir. Nov. 17, 2020) amplifies the importance, per Rule 702, for experts to base their opinions on sufficient facts, including accounting for obvious alternative explanations. The ruling also reminds experts to keep their opinions within their area of expertise when participating in legal matters.

    An Industrial Dispute

    The case in question focused on a product liability dispute and alleged negligence leading to a workplace injury. The plaintiffs, Joseph Hirchak and his wife, sued industrial product distributor, Grainger Inc., after a sling carrying steel tubing broke and fell onto Mr. Hirchak, injuring him while on the job at manufacturing plant, Weiler Inc. In the complaint, the plaintiffs bring product liability and breach of warranty claims against Grainger, alleging its negligence in manufacturing and providing the sling to Weiler caused Mr. Hirchak’s injuries.

    The district court granted the defendant’s motion for a summary judgment motion after throwing out the Hirchaks’ expert witness testimony that the defective sling was a Grainger sling sold to Weiler. The court found that the expert failed to account for “obvious alternatives” to the factual claim that the sling at issue was a Grainger sling. The plaintiffs appealed, arguing that the district court’s summary judgment was inappropriate because the court erred in excluding their expert’s opinion.

    Manufacturing Examination

    The district court, and later the appellate court, took issue with the expert’s claim that the sling in question was manufactured by Grainger. During the time period under examination, Grainger Inc. purchased slings from another manufacturer, Juli Sling Co., Ltd., and distributed them under the brand name, Dayton. To determine the origin of the sling in question, the plaintiffs’ expert performed infrared spectroscopy, chemical, and microscopic analysis that showed similarities to a Grainger-distributed Juli sling and another Grainger-distributed sling furnished by Weiler. Based on his observations of similarities among the tested slings, the expert concluded the sling at issue was distributed by Grainger. The district court found that the expert’s analysis “provided a factual basis for, at most, the premise that the subject sling was a Juli sling.” However, the court also explained that the sling could have been a Juli sling distributed by one of Grainger’s competitors—an alternative the expert failed to consider.

    The appellate court agreed with the district court’s exclusion of the expert’s testimony, stating that the expert opinion itself—not just one of its several premises—must be “based on sufficient facts.” Here, the court said that even if the expert supported his first premise that the subject sling was a Juli sling, he failed to provide the sufficient factual basis that the sling was also a Grainger-distributed Juli sling to satisfy Federal Rule of Evidence 702(c).

    Analytical Gaps in Expert Testimony

    The Hirchaks claimed that the record provides factual support for their expert’s second premise, thus filling the analytical gap in his opinion. They argued that the record showed a known Grainger-distributed Juli sling was found in Weiler’s possession after the accident. The plaintiffs assert that with his specialized knowledge, their expert could then presume that the other slings in Weiler’s possession must also be Grainger-distributed slings, including the subject sling.

    The appellate court disagreed. The court did not rule on whether or not the record contains sufficient evidence to support the additional step in logic to conclude that the subject sling was a Grainger sling. Rather, the judge determined that the expert’s specialized knowledge did not help him take that second analytical step to conclude that the subject sling was a Grainger sling. Thus, his opinion in the record where he made this presumption was impermissible. The judge stated that “[T]he Hirchaks’ argument presupposes that the record can rescue an expert opinion from inadmissibility by filling its analytical gaps. But this is not the law.” An expert must limit their testimony to their specialized knowledge in helping the trier of fact.

    The appellate court upheld the summary judgment, finding that the district court had not abused its discretion in excluding the Hirchak’s expert’s opinion that the subject sling was a Grainger-distributed sling.

    Key Expert Takeaways

    This case highlights the importance of selecting highly experienced and qualified experts who are able to adhere to the requirements of FRE 702. Thorough vetting helps to ensure your expert is well-equipped to provide robust analysis in your case—including considering all alternative explanations. Experts must support their conclusions with sufficient evidence or risk having their testimony excluded entirely.  In the Hirchak case, the expert erred not just in basing his opinion on inadequate facts, but also in making logical leaps in his conclusions—which the court deemed to be analytical gaps. To help the trier of fact, an expert’s opinion must present sufficient evidence and not stray beyond their specialized knowledge, nor make conclusions that should be left to the jury. For these reasons, it’s crucial to recruit experts with confidence. Expert Institute’s Expert Search service provides custom-sourced experts that will meet your case’s precise needs. With the right support, worry over finding the right caliber of expert or strength of their analytical rigor will be a thing of the past.