The Electronic Observer in Your Car

A similar device installed in motor vehicles can provide data about a road crash. How fast was the vehicle moving? Was the driver’s foot on the gas or the brake? How big a jolt did the occupants suffer? Were they wearing their seat-belts?

Knowing what was happening in the vehicle just prior to a crash is of tremendous value to collision investigation experts as they analyze causes and recommend preventive measures. Such information also enables automobile manufacturers to design safer vehicles.

Event Data Recorders

Many vehicles now on the road are equipped with a module that records the last few moments leading up to a crash. Several vehicle manufacturers use the technology. For example, General Motors has had the modules in all its models since 1999, and Ford since 2000. Less sophisticated than an airliner’s black box, the Event Data Recorder (EDR) is part of air bag deployment systems. The GM devices record vehicle speed, engine speed, brake application, throttle position and whether the seat-belts were fastened.

This technology is a tool to analyze collisions with a view to improving safety and efficiency. In the 1970s, vehicle manufacturers used it to collect data to improve design and diagnose systems. Precise, accurate data from collisions helps engineers improve vehicle and highway systems, provides valuable input for regulation and enforcement, and gives insight into driver behaviour in crash situations.

Installing EDRs in fleets, with the knowledge of the drivers, has been shown to reduce collisions. A 1992 study by the European Union found that EDRs reduced the collision rate by 28 per cent and costs by 40 per cent in police fleets; the drivers knew they were being monitored. Most North American drivers, however, do not realize an electronic device may be monitoring their driving, despite the fact this is explained in their owner’s manual.

Reliable and Objective

Despite a few unresolved issues, police and collision reconstruction experts are already using these devices, with the permission of the owner or by means of a court order.

In 2001, a speeding Montreal driver smashed into a car, killing a young man. Without skid marks there was no way to calculate the car’s speed before impact, and only the suspect’s testimony about his own actions. The EDR showed that the vehicle was traveling 157 km/h (in a 50 km/h zone), that four seconds before impact the driver floored the gas pedal, and that just before impact he took his foot off the gas but did not brake. Despite the EDR evidence, the driver was acquitted of criminal negligence causing death, and convicted instead on the lesser charge of dangerous driving causing death.

In another case, the data proved a possible suspect was innocent. When a chain-reaction crash on an Ontario highway ended in the death of a child, witnesses blamed a speeding car. The driver of that car gave police permission to download the data on his EDR, which showed he was driving slowly and quite properly.

If a driver blames a crash on vehicle malfunction, the EDR serves as a reliable electronic observer, confirming (or not) the driver’s behaviour and reactions, and how the vehicle performed.

Numerous “mystery crashes” occur every year — fatal single vehicle incidents with no witnesses. Perhaps the road was slippery, or the driver fell asleep at the wheel. Perhaps the crash was intentional. Investigators can only provide an educated guess about contributing factors. With EDR data, they may be able to solve some of the mysteries.

Due to the unique designs used by each manufacturer, there is currently a lack of standardization. As a result, EDR data cannot be easily retrieved at the crash site. This means paramedics cannot yet take advantage of the information, which could help them make lifesaving decisions.

Looking into the future, the Canada Safety Council hopes emergency responders will someday be able to access the data. This would help them determine the most suitable treatment based on the actual severity of impact, thus potentially saving even more lives and reducing the long-term damage from serious injuries. Currently, GM’s OnStar reads crash severity and enables EMS personnel to respond with appropriate priority.

Ownership and Privacy Issues

Questions must also be resolved about who owns EDR data, who can access it and for what purposes. There are also concerns about privacy and admissibility in court. The legal community in Canada has expressed the opinion that the data in EDRs are the property of the vehicle owner and cannot be accessed without the owner’s consent or unless ordered by a court.

Legislators will need to address these issues in the near future. Reliable, objective crash data from EDRs are critical to further advancement in the science of traffic safety.

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