That is where a heavy truck’s Event Data Recorder (known in the industry as an “EDR”), and often commonly referred to as a “black box” can be very useful. This piece of electronic equipment, while not required by law to be present in all vehicles, at this time, often is present and can be very helpful in accident reconstruction.
The Types of Data That May Be Recorded in a Truck’s EDR That Help in Accident Reconstruction
There are many types of EDRs, and therefore they do not all record exactly the same type of information in exactly the same manner, although NHTSA (National Highway Traffic Safety Administration) does have some standards and rulings for these recording devices.
Some of the types of data that an EDR may record, and which may be helpful for accident reconstruction, include the following:
- Acceleration rate
- Engine revolutions per minute (RPMs)
- Gear selection and/or clutch application
- Engine malfunction information
- Airbag deployment information
- Measured changes in forward velocity (Delta-V)
- Engine throttle
- Brake application
- Steering angle
- Whether seatbelts were on or off
- Sudden stops
- Low oil pressure
- Coolant loss
- Cruise control status
- Fuel economy
- Idle time
- Average travel speeds
Passenger Vehicles Often Have an EDR Too
Not only do many heavy trucks have these black boxes, but often many passenger vehicles may have them as well. Typically, but not always, these EDRs record less information than those within heavy trucks, but still tend to include information used to calculate airbag deployment and seat belt tensioner calculations, for example.
Just as attorneys for injured victims in truck accidents may request the information from an EDR, so too can plaintiffs receive requests to have their data downloaded and analyzed. It can be important for injured parties to have legal representation in such instances to determine what is, and is not, relevant and admissible evidence and what must be provided during discovery.
Expert Testimony Necessary to Interpret and Present This Evidence in Court
The information contained in the black boxes can be used for accident reconstruction, and it is typically downloaded directly from the vehicle(s) involved in the accident soon after the accident occurs. It is important to make sure you obtain legal representation as soon as reasonably possible after an accident occurs to make sure all relevant data is downloaded before it becomes unavailable, lost or destroyed.
Once the information is downloaded into a report it must be analyzed and interpreted by an expert in accident reconstruction to understand what the data means, and to draw conclusions about how the accident occurred (and potentially why it occurred). An experienced truck accident attorney will be able to contact such experts to evaluate the data involved in your case.
Courts often hold that this EDR data is generally accepted and reliable, which meets the requirements for its admission into evidence. However, there are often legal arguments on both sides regarding what the expert can, and cannot say, in regard to conclusions based on the data retrieved. This requires an understanding of evidentiary law, as it relates to expert testimony, to determine which conclusions are appropriate for a jury to hear from an expert.