Negligent Axle Repairs Allegedly Cause Truck Accident

Zach Barreto

Written by
— Updated on July 22, 2019

Mechanical Engineering Expert

Court: United States District Court for the District of Minnesota
Jurisdiction: Federal
Case Name: Vigilant Ins. v. North Suburban Towing
Citation: 2018 U.S. Dist. LEXIS 163031


In December of 2014, an employee of Relay House, Inc. contacted Boyer Trucks and asked them to tow a broken satellite uplink truck for repair. Boyer Trucks retained the defendant, North Suburban Towing, Inc., to complete the tow. North Suburban sent an employee to tow the truck, but rather than towing it, he attempted to make repairs to the vehicle. After making some changes to the driveshaft, the defendant’s employee asked Relay’s employee to test drive the vehicle. During the test drive, the rear axle assembly completely separated from the truck, causing damage to the truck and its contents.

The truck and its contents were insured by plaintiffs Vigilant Insurance Company and Federal Insurance Company. Relay made claims under both the plaintiffs’ policies. The plaintiffs made the required payments and became subrogated to the rights of Relay. They sued the defendant for negligence, claiming that the actions of the defendant’s employee caused the damage.

The Expert

The defendant hired an expert mechanical engineer to review the plaintiff expert reports, claim files, photos taken by the adjusters, and deposition transcripts. The expert was a licensed mechanical engineer, had used his engineering degree in the automotive industry for more than 16 years, and was involved in multiple relevant professional associations. He also did extensive work with vehicles and their component-parts, including investigative work in those areas.

The mechanical engineering expert concluded that the damage to the vehicle was inevitable due to pre-existing problems with components on the underside of the vehicle, specifically the U-bolts and rear axle. He further concluded that the truck would likely have suffered the same fate had it been towed as planned.

This matter was before the court on the plaintiffs’ motion to exclude the expert’s testimony. The plaintiffs argued that the mechanical engineering expert’s testimony should be excluded because he was unqualified, he did not inspect the truck or components in person, his analysis was based on conclusions made by others, and that his opinion did not address the potential fault of the defendant’s employee.

Courts Discussion

The plaintiffs contended that the defendant’s mechanical engineering expert was not qualified because he had never worked with or operated tow trucks. The plaintiffs further claimed that the expert primarily worked in vehicle fire investigation, and thus, had insufficient experience outside of his education to opine on the issues at hand. The court concluded, however, that overall, the expert’s education and experience showed that he was qualified to express his opinions on vehicular components and their importance in this case. The fact that he had not investigated a situation exactly like the one at hand in the past did not render his report and testimony irrelevant.

The plaintiffs next argued that the expert’s testimony was inadmissible because the expert did not inspect the truck first-hand. The court considered this argument as meritless. The mechanical engineering expert had no opportunity to inspect the damage in person because the mechanics had fixed the truck and discarded the damaged parts before this lawsuit was initiated. The court drew attention to the fact that the plaintiffs had disclosed an expert to conduct an investigation after the truck was repaired. By this logic, the plaintiffs’ argument would call for the exclusion of their own expert witness as well as the defendant’s. The defendant mechanical engineering expert admitted in his report that his findings were imperfect because he did not see the truck or components first-hand. However, the court felt that his report and testimony would still assist a jury with facts in issue. His lack of first-hand knowledge could be addressed on cross-examination.

The court also concluded that forming expert opinions and conclusions with the help of statements and writings from others also does not mandate exclusion of those expert opinions. The mechanical engineering expert’s report was based on photos taken of the vehicle and its components shortly after the accident, statements from insurance adjusters and mechanics, and deposition testimony from those present at the time of the damage. Despite these shortcomings, which the expert acknowledged, the reliability of the expert’s opinions and methods were bolstered by the fact that another mechanical engineer at his company peer-reviewed his report. Although the mechanical engineer relied on statements and information provided by others, he used that information to explain the component parts involved and the factors at play and provide a conclusion. The court found that the materials the expert used were a sufficient basis for his testimony.

The plaintiffs also took issue with the mechanical engineering expert’s failure to focus on the background and training of the defendant’s employee. Although the court noted that testimony is only admissible if the expert’s specialized knowledge can help the trier of fact to understand the evidence, Fed. R. Evid. 702(a) Rule does not require that the testimony assist the jury with all facts. Mercado’s report and testimony addressed the root cause of the damage to the vehicle, and whether the damage would have occurred had the vehicle been towed. These were certainly facts in issue.

The expert’s opinions were helpful to a jury because he explained, among other things: (1) the location, function, and importance of the relevant truck components; (2) how these components interact with other components on vehicles like the one in question; (3) how these components can fail, and the consequences if they fail; and (4) his opinion on the likelihood of these components failing during a tow. The court held that if the plaintiffs believed the expert failed to consider all relevant factors in forming his opinion, that was a matter for cross-examination.


The mechanical engineering expert’s testimony and report were deemed relevant to the case. Accordingly, the plaintiffs’ motion to exclude the defendant expert’s testimony was denied.

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