An intelligent airbag looks likely to prove a key witness in the case of a 26-year-old Canadian driver who killed another driver while speeding along a Montreal street.

Although the inflatable friend may have saved Éric Gauthier's life in the crash, it later sang like a canary, revealing that the young man had been travelling at three times the 50kmph speed limit. 20-year-old student Yacine Zinet died in the incident when his car was struck.

Gauthier's Chevrolet Sunfire carried a recording device - known in the trade as a EDR, or event data recorder. EDRs are now commonly fitted to new cars and are intended to protect manufacturers against faulty airbag lawsuits. Police called on the digital evidence because there were no skid marks at the crash scene to indicate how fast Gauthier had been travelling.

There is increasing disquiet among drivers about such "snooper" devices. Last November, the FBI forced the operators of one stolen vehicle's on-board vehicle navigation system to enable it as a covert eavesdropping device. The courts were not impressed. In California, a new law means that anyone who buys a car after June must be informed of exactly what data any fitted EDR can record. Commonly, EDRs are simply a memory chip "loop" system, which continually records and re-record five seconds of data such as speed, rpm, etc.

In Gaulthier's case, this last five seconds of data proved critical. He attended a pre-sentence hearing yesterday, having been already convicted on two counts of dangerous driving. The prosecution is demanding three years' jail. ®

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