A friend, who was recently involved in a relatively minor auto accident, asked me why his insurance company wanted to download information from his vehicle’s onboard computer system.

I replied they probably wanted to know what he was doing just prior to the accident — to determine if he was speeding or driving recklessly.

My friend, who is a big believer in personal rights above all else, was flabbergasted.

“They can find out that stuff from the car?”

Depending on the car, the answer is a definite yes.

As vehicles have become more sophisticated and systems monitor nearly all functions, it’s possible to reconstruct what a driver was doing just prior to an impact.

It’s done by capturing data about speed, braking and steering input from what is called an event data recorder. And it’s going to get even more complex — already there are systems on some cars that warn when there’s a vehicle in a car’s blind spot, as well as anti-collision warning systems like the one currently featured in a Volvo commercial.

In a lawsuit, an attorney could make much of data that showed, for example, that a car had warned the driver of a stalled car ahead and the driver did nothing to avoid it.

The Big Brother aspect of all this is, in some regards, an outgrowth of increasingly sophisticated maintenance and emissions monitoring.

Some manufacturers have found it cost effective and desirable to install all manner of monitors in late-model vehicles. The upside is that these wide-ranging monitoring systems can make it easier for technicians to diagnose thorny problems that occur intermittently, or determine what systems might have been compromised in an accident.

As a safety feature, systems like General Motors’ OnStar can detect an airbag deployment and notify rescue crews. GM is promising a new generation of OnStar that will be able to transmit to rescue workers more detailed information about a crash such as: the direction of the impact, whether the car rolled over, whether there was a change in speed, and other data.

But in our litigious society, some car owners are worried that their vehicles are tattletales, ready to rat them out for driving 20 mph over the speed limit.

Proponents of privacy rights argue that a car should not become a witness for the prosecution.

But the issue isn’t that clear cut.

The National Transportation Safety Board wants so-called black boxes made mandatory so that researchers and regulators can collect data to help create new safety technology.

For today’s car buyer who is concerned about this issue, finding out what the car knows and who it might tell is not an easily answerable question.

The National Highway Traffic Safety Administration issued a rule last August requiring automakers to tell new-car buyers if an event data recorder has been installed — but the rule doesn’t take effect until model year 2011 cars.

In 2004, California passed a law requiring manufacturers to disclose whether there is an event data recorder onboard and took the additional step of banning the download of data from the recorder without the owner’s permission or a court order.

Some other states have followed California’s lead, but until the federal rule takes effect there’s no universal disclosure. And there’s no federal rule about disclosure when the vehicle changes hands as a used car.

So in 2007, the best course of action for a car buyer is to ask questions of the dealer’s service department, which should have specific information on what data the car tracks.

Here are this week’s reader questions:
Car’s onboard data system could haunt you
Do the same dealer fees apply when buying or leasing?
Should I use my savings to pay off my car loan?
Is it better to pay cash or finance a new car?

If you have a question for Terry, e-mail him at
Driving for Dollars.

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