3M Expert’s Opinions Partially Excluded from Earplug MDL Bellwether

A Florida federal judge has excluded opinions from a 3M expert witness in the ongoing CAEv2s combat earplugs bellwether trial. In this case, the plaintiffs claim they suffered injuries to their hearing due to defective earplugs used during military activities. Here, the plaintiffs asked Judge M. Casey Rodgers to exclude the expert’s testimony on behalf of 3M ahead of the trial. The judge agreed in part and disagreed in part on the plaintiffs’ challenges to this expert witness.

The Defendant’s Expert

The defense’s expert currently serves as President and Principal Consultant of Driscoll Acoustics, LLC. The company specializes in “noise measurement, noise exposure assessment, noise control engineering, and hearing loss prevention.” He has worked as an acoustical consultant since 1998 and is a mechanical engineer and board-certified noise control engineer. He obtained his Master of Science degree in mechanical engineering in 1980.

The Expert’s Opinions

3M employed the expert to provide several opinions on plaintiff McCombs’s hearing injuries and use of hearing protection devices during his military service. The expert opined that McCombs faced a “significant risk” for noise-induced hearing loss and tinnitus after a close-range explosion during his military service in Afghanistan. However, he also opined that McCombs “does not have noise-induced hearing loss (NIHL) as a result of his military service”. Lastly, the expert gave his opinion that “[t]he audiograms of Mr. McCombs support that the hearing protection devices he used during his service protected his hearing.”

The Plaintiffs’ Exclusion Challenge

In seeking to exclude the testimony, plaintiff McCombs argued that the expert was not qualified and did not use a reliable methodology to support his causation opinion on McCombs’s tinnitus and “related injuries.” McCombs also asserted that other parts of the opinion would not be helpful to a jury.

Judge M. Casey Rodgers established that this exclusion challenge required the “qualification, reliability, and helpfulness” test. In addition, under Rule 403 a court must consider if “the probative value of otherwise admissible evidence is substantially outweighed by its potential to confuse or mislead the jury, or if the expert testimony is cumulative or needlessly time-consuming, or if it is otherwise unfairly prejudicial.”

The Court’s Ruling

The judge ruled that 3M’s expert was not qualified to opine that McCombs does not have noise-induced hearing loss as a result of his military service. In the court’s view, the expert wasn’t qualified to offer a diagnosis since “he is an engineer, not a medical doctor or audiologist.” The judge added that the expert has no medical education, training, or experience, and has never treated or diagnosed tinnitus or hearing loss in a patient.

No Reliable Methodology

Nor was the judge convinced that the expert used a reliable methodology for his specific causation opinion on McCombs’s injuries. At his deposition, the expert testified that he was “citing the medical experts’ opinions” and “[r]elying on the evidence of other experts and their conclusions with regard to Mr. McCombs’s hearing status” in reaching his opinion. He did not apply his own expertise to analyze the medical experts’ opinions and reach his own opinion. The judge concluded that there was no reliable methodology supporting the opinion that McCombs does not have noise-induced hearing loss from his military service. Thus, the expert’s specific causation opinion was inadmissible.

No Insight Added

The court also agreed that portions of the expert’s testimony were unhelpful and inadmissible under Rules 403 and 702. Specifically, the court threw out opinions relying entirely on McCombs’s audiograms. The expert used these records as justification that McCombs’s use of hearing protection devices was effective in protecting his hearing.

A Choice for the Jury

The court, however, did not entirely exclude the expert’s opinion. The plaintiffs’ asserted the expert’s opinions on peak sound pressure McCombs would have experienced during the explosion were contradictory and confusing for a jury. The judge disagreed. Although the expert’s own definition of noise reduction ratings contradicted industry standards, this is not grounds for exclusion. Such a contradiction would go to an expert’s credibility which is the province of the jury.

Impact on the Bellwether

The expert’s exclusion could impact the defense’s case. The court threw out key portions related to specific causation and dispute of plaintiff McCombs’s noise-induced hearing loss. On the other hand, perhaps the opinions on the peak sound pressures may sway a jury in 3M’s favor.

Overall, plaintiffs will want to make sure their experts are qualified for the specific opinions they give in a case. In particular, it’s important to verify an expert is not merely relying on and repeating other expert’s findings.