EDR could be either an eye-glazing acronym or the difference between you and the other driver paying huge sums of money or going to jail. And it's getting lots of attention since a Montreal man was sentenced to 18 months on evidence from his car's event-data recorder.
The revelation of the existence for a decade of the automotive event-data recorder is almost as momentous in traffic-law and civil-court terms as finding DNA was in criminal law.
If your vehicle has airbags, if you have a smart adjuster or lawyer and providing you don't drive like a maniac, proving who is in the wrong can be a lot easier.
But, if you're a little paranoid, certain that there is a Big Brother and that you're the object of his attention, and you drive on the wild side, you could see the EDR as part of a conspiracy to stick it to Canadian drivers.
As with many things in an increasingly complex world, there's no totally yes-and-no answer.
The benefits of the computer that monitors your drive system, of a global positioning system, and of toll transponders, are immediately obvious.
For most drivers and even most mechanics, the upside of the EDR's electronic forensics can be a little more obscure.
"If they're in there, I don't know where the hell it is," says Mark Ridout, service manager for Polito Ford in Lindsay, Ont.
Ford started installing the device colloquially known as "the black box" in vehicles in 2000, six years after General Motors adopted what was ostensibly a monitor of the airbag system. With such a specific function, it's small wonder manufacturers didn't rush to feature the system and the average mechanic doesn't understand it.
What references that professionals such as Ridout and ordinary drivers find to the device in manuals tend to be oblique.
"The data that is recorded is of no interest to service managers or auto repair. There is nothing in there regarding the diagnostic of any system except for performance during a crash. The data is of interest to safety systems researchers, auto makers to improve the crash characteristics of cars and attorneys for either civil or criminal litigation," says Jim Harris.
He's a principal of Harris Technical Services, a Florida-based accident reconstruction company that works for police, insurance companies and lawyers, and is a major user of EDR data.
There are a growing number of such companies in North America, staffed by people with various backgrounds, including engineering, policing, aircraft systems and data analysis, all focused on determining how crashes happen and can be prevented. As a byproduct, but of increasing interest, they also help determine who or what caused a crash.
So what is the box and why is it sitting in so many vehicles without owners knowing it even exists?
Accident researchers were limited to crash tests using dummies, or collecting data on individual crashes and compiling it in databases, but both methods had limitations.
As electronics shrank, however, and since airbags are totally dependent on sensors, the opportunity to collect both crash data and monitor the effectiveness of the bags became feasible. Hard, accurate data with real people in real crashes could be recorded and analyzed.
The EDR, a four-inch-square box, similar to recorders on airplanes and trains, can tell investigators the car's speed, engine speed, how far the accelerator was depressed, whether brakes were applied, whether the driver wore a seatbelt, and what warning lights were on, from about five seconds before impact.
When an airbag deploys, the data are recorded on a computer chip. When a near-deployment occurs, the information is stored for 250 engine starts.
A second impact can be recorded in a non-deployment file, depending on circumstances and the time between collisions.
Harris predicts the insurance industry and legal community will push for EDRs in all cars.
"As long as the data is limited to crash events, I have no problem with this. It should also be noted that EDR evidence does not, cannot, must not, stand alone. It has to be considered with physical evidence and given the appropriate weight. EDR and sensor malfunctions have been found."
Toronto lawyer Clayton Ruby, Stephen Keating of the University of Denver's privacy institute, and the Ontario privacy commissioner have been among those to raise civil rights concerns over EDRs, but there seems an equally strong group that favours the benefits the boxes bring.
Both the American National Highway Traffic Safety Administration and the Canada Safety Council have found the EDR a useful tool, while recognizing concerns about ownership of data and a lack of standardization of systems makes emergency staff at an accident unable to use it to determine how to proceed.
"Looking into the future, the Canada Safety Council hopes emergency responders will some day 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," the council says in a position statement.
It says "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."
In 2001, the speeding Montreal driver smashed into a car, killing a young man. Without skid marks there was no way to calculate his speed, and there was only the suspect's testimony about his actions. The EDR showed his vehicle going 157 km/h in a 50-km/h zone, that four seconds before impact he floored the gas pedal, and that just before impact he took his foot off the gas but did not brake.
In another case, according to the safety council, data proved a suspect innocent. When a chain-reaction crash on an Ontario highway killed a child, witnesses blamed a speeding car. The driver allowed police access to his EDR, which showed he was driving properly.
"It is important to keep in mind EDRs have been introduced by the prosecution (the Montreal case) which resulted in a conviction and by the defence (Florida v. Walker) which resulted in an acquittal. EDRs can cut both ways," Harris said.
In Europe, there have been proposals to use the technology to monitor drivers and fine speeders.
As far as other monitors in cars, there are lots. Cars have become computer networks that also happen to have an engine and four wheels. There are engine, transmission, brake, fuel, air, and electrical monitors throughout and they all communicate with others in one form or another.