Every detail matters when proving fault in a car accident, including how your vehicle’s safety systems perform. Lawyers can use the information in the car to reconstruct accidents and determine liability.
Car accidents can be stressful, traumatic experiences that leave victims with serious injuries and high bills. In 2023, the average auto liability claim for bodily injury was $26,501, while the average claim for property damage was $6,551. If someone else’s negligence caused your accident, you may be compensated for the damages you have suffered. However, you will need to present evidence to prove who is at fault and, therefore, financially responsible for the damage.
When considering court evidence in an accident suit, most people think of photographs, police reports, eyewitness accounts, and medical records. However, there are other lesser-known types of evidence that can help your case. It’s easy to view seat belts, airbags, and crumple zones as just life savers, but these and other vehicle systems can also play an important role as evidence in personal injury or accident litigation.
Seat belts as evidence
Whether or not you were wearing a seat belt may affect your case, especially if you live in a state with a seat belt defense rule. If you weren’t wearing a seat belt, this rule can reduce your damages, because the defendant can argue that you were partially responsible for your injuries (a concept known as contributory negligence). In some states, seat belt evidence is inadmissible to prove negligence, although it can be presented for damages.
If you were wearing a seat belt at the time of the accident, you will need to prove it. There are different ways to do this, such as:
- Supplying the court with dashcam footage of the driver or taxi facing the driver.
- Submitting the seat belt sensor data shown to you.
- Providing testimony from accident witnesses or first responders showing that you were wearing a seat belt.
Although seat belt evidence does not prove fault, it can show that you took the necessary steps to protect yourself.
The crumple zone as evidence
Almost all cars and trucks are designed with crumple zones, which are engineered to absorb crash energy. Crumple zone data can be presented as evidence, especially if they failed to perform as expected, and contributed to your injuries.
There are a few ways you can use your vehicle’s crumple zone as evidence to support your compensation claim. One is to submit crash reports and photos of the damage to your vehicle. Another is to have accident reconstruction experts analyze your vehicle’s crumple zone performance.
If the crumple zone worked as expected, it could be argued that your injuries were less severe, potentially reducing the amount of compensation and medical expenses. However, if the crumple zone was defective and contributed to your injuries, you may be able to file a product liability claim against the vehicle manufacturer.
Airbag and deployment data as evidence
Airbag deployment data can play an important role as evidence in your car accident court case, as the safety system can be helpful or harmful. For example, an airbag that deploys correctly may prevent a serious injury or save your life, but one that deploys accidentally, late, or not at all may be a contributing factor to the crash and your injuries. Stored in the vehicle’s event data recorder, airbag deployment data provides a clear picture of when an accident occurred, helping to establish fault.
A car accident attorney can use this data to determine the severity of the impact, the speed you were traveling, and whether the airbags worked as intended. If they can prove that the airbag helped limit your injuries, you may get less compensation. However, if the airbag is found to be defective, you may be able to file a product liability claim, as the vehicle manufacturer will be partially responsible for the severity of your injuries.
Event Data Recorders (EDRS) as Evidence
While most people have heard of black boxes used as evidence in plane crashes, many people don’t realize that most modern vehicles are equipped with similar technology. Event data recorders (EDRs) or electronic control modules (ECMS) record information such as seat belt use, throttle, speed, braking, and seconds before, during, and after airbag deployment.
This data can be downloaded from the EDR to help reconstruct what happened in the vehicle during the crash. Submitting your own EDR data is acceptable, although due to privacy concerns, you may not submit another driver’s EDR data unless it has been legally retrieved. The court may present this information in certain cases, such as personal injury, criminal DUI, or wrongful death.
If you or another party wishes to introduce EDR data as evidence, it is important that you are aware of the possibility that it may be challenged on the grounds that:
- Experts may testify negatively about the calibration or maintenance of vehicles.
- EDR data is not accompanied by accident scene measurements, photographs of vehicle damage, or eyewitness accounts.
- The EDR did not record the information correctly when the accident occurred.
Due to the evolution of case law around the US, lawyers who wish to use EDR data need to be particularly careful about the chain of custody for this data and rely on experts who are qualified to evaluate it, as it may be inadmissible in court.
Other surprising sources of evidence
In addition to seat belt, crumple zone, and EDR data, you will be able to present other evidence in the case of your vehicle accident. Other possible sources of evidence include:

- Mobile phone records: Provided cell phone records are obtained legally, they can prove that a party was calling, texting, or using an app when the accident occurred. By providing evidence of distracted driving, they can strengthen or weaken your case.
- Collision Warning/Lane Assist Logs: These logs can provide evidence that shows whether you or another driver has ignored warnings.
- Defective vehicle components: If your vehicle’s brakes, steering column, or other components are found to be defective, the manufacturer may be liable.
Support your case with strong evidence
Whether you are the victim of another driver’s negligence or you are being blamed for a car accident, you need to support your case with strong evidence and expert legal advice.
An accident attorney knows how to gather evidence, investigate, and challenge unfair allegations, increasing your chances of receiving compensation for damages or being found only partially responsible or innocent. The more evidence you have, even if it’s from surprising sources, the more likely you are to be able to move on with your life sooner.
