Motor Vehicle Collision Fatality Allegedly Caused By Mechanical Seatback Failure


Mechanical Engineering Expert

Court: United States District Court for the Eastern District of Texas, Sherman Division
Jurisdiction: Federal
Case Name: Zoch v. Daimler, A.G.
Citation: 2018 U.S. Dist. LEXIS 164500


This products liability case involves the alleged failure of a 2008 Smart Fortwo car which resulted in the death of the vehicle driver.  The plaintiff filed a negligence suit on behalf of deceased claiming there were defects in both the design and manufacturing of the driver’s seat which led to the death of the plaintiff during the collision.

The Mechanical Engineering Expert

The plaintiff retained a professional mechanical engineer with expertise in automotive safety. The expert provided testimony that the vehicle was defective and unreasonably dangerous due to the design of its cabin structure and seating system. The expert also claimed that the defendants were negligent in their actions and omissions related to the design of the subject vehicle.

The expert was a registered professional engineer who held a mechanical engineering degree and had authored 15 publications on automotive structure and design. At the time of the case, he was employed as a senior engineer at a safety analysis and forensic engineering firm. In this role, the expert “researched, designed, implemented, and tested alternative automotive safety systems and published automotive safety technical publications.” The expert was also routinely called upon to evaluate vehicle accidents as well as test and evaluate various vehicle safety systems.

The expert opined that at the time when the vehicle had been designed and manufactured,  alternate seat designs were available which would have been non-defective and safer. The expert also conducted three sled tests to demonstrate that replacing the luggage compartment cover bar with a structural steel tube would have been a safer alternative design for the vehicle. The defendant filed a motion to exclude the testimony of the plaintiff’s expert claiming the expert lacked the necessary background to testify as an expert.

Court Discussion

The defendant claimed that the expert had never worked for an automobile manufacturer and had never been involved in the design of vehicle seats or structures for commercial vehicles. However, the court noted that the expert’s curriculum vitae listed various roles he held which involved analyzing automotive structures and seat design. As such, the court found that the expert possessed the necessary background, training, education, and experience to testify regarding automotive structure and seat design.

The defendants argued that the expert provided no reliable testing, nor a correct understanding, nor sound analysis of the subject accident to support the following proposed alternatives: 1) bulkhead reinforcement; 2) high retention seat back; 3) pelvic catcher; 4) dual recliner; and 5) ABTS/SIR design. The plaintiff claimed that the defendants misapplied the standards of proof and ignored testing performed by the expert. The court found that the expert’s safer alternative designs were admissible as he provided adequate explanation and testing on each alternative design to demonstrate they were safer.

The defendants argued that the expert’s sled tests were unreliable and inadmissible because he used a reclined angle set by another one of the plaintiff’s experts. The defendants also claimed that the velocity changes of the sled tests were less than the velocity change determined by another one of the plaintiff’s experts and further criticized that the expert failed to consider different accident scenarios. However, the defendants could not explain why these factors rendered the expert sled tests unreliable or whether altering these variables would change the expert’s results.

The defendants also contended that the expert did not provide evidence that his proposed safer alternative designs were economically feasible when the vehicle was designed and manufactured. However, the corporate representative for the defendants’ seat supplier had testified that they had the technical capability to offer alternatives if needed.


The court found that the defendants’ seat manufacturer was capable of producing and incorporating any number of alternative designs requested by the defendants. The court denied the defendants’ motion to exclude the testimony of the plaintiff’s mechanical engineering expert witness.