🚀 Medical Chronologies – the fastest way to summarize medical records!

Plaintiff’s Forensic Engineering Expert Witness Admitted in Catastrophic Rollover Case in Maryland Federal Court

Kristin Casler

Written by
— Updated on June 22, 2020


Darin Ruark v. BMW of North America, LLC, et al., No. ELH–09–2738, U.S. District Court District of Maryland; January 30, 2014


Darin Ruark was 17 in 2006, when the 1995 BMW 325is coupe he was riding in rolled over several times. Although he was wearing his seat belt, his head struck the roof of the car. He suffered a catastrophic neck injury that rendered him quadriplegic.

Ruark filed suit against BMW of North America, LLC, the vehicle distributor, and BMW AG, the manufacturer. He alleged the car was defective and unreasonably dangerous because the occupant restraint failed to keep him firmly in his seat, and because the strength-to-weight ratio (SWR) of the roof was deficient, causing the roof to intrude into the passenger compartment during the rollover.

Regardless, BMW maintained that the SWR met federal standards and that the roof intrusion occurred after Ruark was already injured. It argued that a stronger roof would not have prevented Ruark’s injury.

The case settled on May 21.

Forensic Engineering Expert Witness:

Ruark retained Dr. Stephen Batzer to provide an opinion on whether the roof of the BMW was defective or unreasonably dangerous. He presented testimony about a reasonable alternative design of the vehicle’s A-pillars, which, according to Ruark, would have strengthened the roof. He opined that at the time BMW designed the vehicle, there were a number of reasonable alternative roof support structure designs that had already been incorporated into various production vehicles.

Batzer examined the police report, the subject vehicle, exemplar vehicles, engineering drawings and specifications for 1995 BMWs, data and reports related to roof strength testing of 1995 BMW vehicles, and numerous documents produced during discovery.

Batzer has a master’s degree in manufacturing systems engineering and a Ph.D. in mechanical engineering. He worked as an engineer for 25 years, specializing as a forensic engineer and failure analyst for over 10 years.

Consequently, BMW sought to exclude much of Batzer’s testimony under Daubert v. Merrell Dow Pharmaceuticals (509 U.S. 579 [1993]) and Federal Rule of Evidence 702.

Admissibility of Forensic Engineering Expert Witness:

The U.S. District Court for the District of Maryland noted that most of BMW’s objections ask the court to decide merits issues or weigh the persuasiveness of certain evidence.

“[T]he possibility that a jury might find an expert’s testimony to be unpersuasive does not render that testimony deficient under Daubert,” the court said. “Put differently, BMW has not adequately challenged Dr. Batzer’s methods or conclusions about the roof strength of the 1995 BMW 325is coupe. Rather, it has questioned whether those conclusions are persuasive evidence that the allegedly defective roof contributed to Mr. Ruark’s injuries. That is a question for the jury.”

Therefore, the court said that the relevant question under Daubert is whether Batzer reliably collected his data with a proper methodology, not whether the conclusions he drew from the data are correct.

“The record demonstrates that inverted drop tests are a scientifically valid method for analyzing roof performance in rollover crashes, even though they do not replicate the precise circumstances of a rollover crash,” the court said.

Batzer relied on numerous published articles that utilized drop tests; he published numerous peer-reviewed articles discussing the use of inverted drop tests to evaluate vehicle performance in rollover crashes, and BMW used inverted drop tests to gather data about the forces that were present on Ruark’s neck during the rollover.

“In sum, Dr. Batzer engaged in significant research, field testing, and statistical analysis of the BMW 325is coupe. His conclusions about the vehicle’s susceptibility to roof crush and about available alternative designs for its A-pillars were not based in conjecture or speculation, but rather were based on scientifically accepted methodologies.”


Leave a Reply

Your email address will not be published. Required fields are marked *

I am an