Reader Question: Data Recorders?

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Here’s the latest reader question, along with my reply!

Gary asks: Assuming a car has a means of collecting and storing data, can the car’s owner access that data? For example, if someone is ticketed for speeding and he or she knows that wasn’t the case, can the car’s owner download the data to prove the case in court? Is data from a vehicle’s computer system admissible in court on behalf of the owner? If not, is it admissible on behalf of the state?

My reply: There’s no assuming – for good or bad. Almost all cars built since the early 2000s have Event Data Recorders (EDRs) which store various data such as speed, throttle input, braking force – and so on. This data can be accessed by anyone with physical access to the EDR and the technological means needed to retrieve it.

If you wreck your car, the government/insurance mafia will possibly try to get the data and (creepy part) the courts have ruled they may do so – even though it is nominally your car. But what’s good for the goose is good for the gander – or at least it ought to be. I see no reason why the data in the EDR could not be used by the owner to defend himself. But you will have to dig the thing out of the car’s guts – and have the necessary reader, to get the data it contains.

Many newer cars also have GPS and that can be used to establish speed at any given time as well as location and so on. The newest cars have real-time (i.e., as you drive) speed monitoring  – and presumably, recording – capability as well. Also brake force application, acceleration and cornering forces. The insurance/safety mafia is pushing hard to have this capability made mandatory and made connected – to them – so as to dun/mulct us in real time.

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Got a question about cars – or anything else? Click on the “ask Eric” link and send ’em in!

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  1. You might try to use a data recorder to prove your innocence, but I seriously doubt any DA or prosecution lawyer worth anything would allow it without some major proof of not being tampered with. And if the case is important enough to warrant the sort of experts who might be willing to sign off on the validity of that data you can bet there will be expert witnesses there to discredit the data anyway. Civilian level (L1) GPS is generally not going to be permitted as the only evidence in court, even in cases involving court initiated tracking.

    With good reason, too. Flight data recorders are sealed with tamper-evident tape and certified to be operational before takeoff. No one is certifying your car’s ECM before you leave the driveway. And who’s to say someone didn’t gain access to your vehicle (do you remember to lock it? Every time? Never forgetting ever?) and install malware?


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