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Determining the Admissibility of Event Data Recorders for Traffic Accident Reconstruction in Illinois


     By Crash Data Services, LLC Accident Reconstruction and Crash Data Retrieval Expert Witness

PhoneCall Shawn Gyorke - Crash Data Services, LLC at (847) 217-6644


Expert Witness: Crash Data Services, LLC
The admissibility of information obtained from vehicle event data recorders (black boxes) has been challenged in many states. This article is intended to explain how EDR data was challenged in Illinois and ultimately accepted.
While the information recorded on event data recorders (EDRs), commonly referred to as vehicle black boxes, is tremendously helpful in determining how a traffic accident occurred and in improving safety, it was not until recently that EDR data was legally challenged in Illinois and ultimately accepted.

The acceptance of EDR data in Illinois stemmed from a car accident in Woodford County on November 6th, 1996. Danielle Bachman, driving a 1996 Chevrolet Cavalier, crossed onto the wrong side of the road and crashed head-on with a delivery van. The cause of the crash was determined to be loss of control on Bachmanís part.

In June 1998, General Motors Corporation recalled all 1996 Chevrolet Cavaliers because of flawed calibration of vehicle sensing and diagnostic modules (SDMs), GMís version of an airbag control module (1). Due to improper calibration, some SDMs, manufactured by Delphi Automotive Systems and Delco Electronic Systems, inadvertently deployed the airbags during low speed crashes or when a relatively small object, such as a stone, struck the floor pan.

Bachman, and her mother, filed a lawsuit (2) in June 1998, alleging that the SDM in Bachmanís 1996 Chevrolet Cavalier was defective, and it was an unintended deployment of the vehicleís airbags that caused the crash. In their complaint, Bachman and her mother noted GMís recall and claimed that the SDM in Bachmanís car was hypersensitive to road surfaces on the day of the crash.

In September 2000, Bachman and her mother filed a motion to bar all testimony and evidence pertaining to the EDR crash data the defenseís experts planned to submit. In October 2000, in response to Bachman and her motherís motion, the defendants requested a Frye hearing. In determining the acceptance of expert testimony with regard to any technology, Illinois generally follows the Frye standard.

The Frye standard was formed after Frye v. United States (3), a District of Columbia Circuit Court case from 1923, which addressed the admissibility of polygraph evidence. Under the Frye standard, it is not enough that an expert testify a particular technique is sound. Frye creates a requirement that the scientific technique must be "generally acceptedĒ by the relevant scientific community. In addition to the Frye standard, the process of assessing whether a technology is new or novel was set forth in Harris v Cropmate (4).

In most jurisdictions, including federal courts, the Frye standard has since been superseded by the Daubert Standard. The Daubert standard was derived from the 1993 Supreme Court case Daubert v. Merrell Dow Pharmaceuticals (5). This more recent standard rejects the need for "general acceptance" and calls for an independent judicial assessment of reliability (6). Under Daubert, the courts often consider if a technology has been peer reviewed and validated in addition to being commonly accepted (7).

During the Frye hearing for the Bachman case, on behalf of the defendants, engineers for both Delphi and General Motors presented evidence that airbag control modules, like SDMs, are commonly used throughout the automotive industry. Engineers went on to explain how the devices control airbag deployment and permanently record information within their EDRs. The defenseís experts testified that based on scientific testing by automobile manufacturers, the National Highway Traffic Safety Administration (NHTSA), Vetronix, the Insurance Institute for Highway Safety (IIHS), and Canadian law enforcement, SDMs were known to accurately and reliably record crash data within their EDRs.

Based on the evidence presented, the trial court ruled that the method of recording data within the EDR of an SDM was not new or novel. The court also acknowledged that EDR crash data was generally accepted within the relevant scientific community. Therefore, the Frye standard was met and the EDR data was consequently allowed at trial.

During the November 2000 jury trial, Bachman testified that her driver airbag had deployed ďout of the blueĒ and that the unwarranted deployment rendered her unconscious before the crash with the delivery van. The defendants offered expert testimony and provided recorded crash data from the EDR contained within the SDM of Bachmanís vehicle. Contrary to Bachmanís testimony, the defendantsí experts concluded that the SDM in Bachmanís vehicle had not malfunctioned and the vehicle deployed the airbags as a result of the collision with the delivery van. The trial court jury ultimately returned a verdict in favor of the defendants and against Bachman and her mother.

In 2002, Bachman and her mother filed an appeal heard by the 4th District Appellate Court of Illinois (8). As the primary basis for appeal, Bachman and her mother argued that the trial court erred in its denial of their motion in limine, which would have excluded the EDR evidence and related opinion testimony.

The appellate court disagreed with Bachman. The trial courtís decision to allow the EDR evidence was affirmed. In the appellate courtís opinion, EDR technology was not new or novel and was generally accepted within its respective field. Thus, the Frye standard had been appropriately applied with regard to EDR technology and legal precedence was set in Illinois.



1 National Highway Traffic Safety Administration (1998) Defect and Noncompliance Notice (Part 573) Assigned Recall No. 98V-146.

2 Bachman, et al, v. General Motors Corp., Uftring Chevrolet-Oldsmobile, Delphi Automotive Systems and Delco Electronics Systems, Ill 98L21 (1998).

3 Frye v. United States, 293 F. 1013 (D.C. Cir. 1923).

4 Harris v Cropmate, 302 Ill App 3d 364, 368-75, 706 N.E. 2d 55, 60-65 (1999).

5 Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (1993).

6 Dixon, Lloyd & Gill, Brian (2001) Changes in the Standards for Admitting Expert Evidence in Federal Civil Cases Since the Daubert Decision. Santa Monica, CA: The Rand Institute for Civil Justice.

7 Jones, Graham R. (2002) Presidentís Editorial Ė The Changing Practice of Forensic Science. West Conshohocken, PA: Journal of Forensic Science.

8 Bachman, et al, v. General Motors Corp., Uftring Chevrolet-Oldsmobile, Delphi Automotive Systems and Delco Electronics Systems, Ill App 4d, No. 4-01-0237 (2002).

ABOUT THE AUTHOR: Shawn Gyorke - Crash Data Services, LLC
Shawn Gyorke is a graduate of Northwestern University's Center for Public Safety and is certified as an Accident Reconstructionist by the state of Illinois as well as the Accreditation for Traffic Accident Reconstruction (ACTAR). Shawn is a member of the Illinois Association of Technical Accident Investigators (IATAI) as well as a member of the Midwest Association of Technical Accident Investigators (MATAI).

Shawn has over 10 years of accident reconstruction experience. He has investigated hundreds of accidents involving fatalities, DUIs, pedestrians, bicyclists, motorcycles and trucks. He has testified in both criminal and civil proceedings and has extensive experience with Illinois Traffic Law.

In 2007, Shawn obtained his certification as both a Crash Data Retrieval Technician and Analyst with Bosch Diagnostics. Since that time, Shawn has been a guest speaker on crash data retrieval for attorneys and insurance fraud investigators.

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While every effort has been made to ensure the accuracy of this publication, it is not intended to provide legal advice as individual situations will differ and should be discussed with an expert and/or lawyer.
For specific technical or legal advice on the information provided and related topics, please contact the author.

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