"Currently, some convicted drunken drivers must use breathalyzer devices attached to an ignition interlock, blowing into a tube and disabling the vehicle if their blood alcohol level is too high. The legislation doesn’t specify the technology, only that it must “passively monitor the performance of a driver of a motor vehicle to accurately identify whether that driver may be impaired.”
Sam Abuelsamid, principal mobility analyst for Guidehouse Insights, said the most likely system to prevent drunken driving is infrared cameras that monitor driver behavior. That technology is already being installed by automakers such as General Motors, BMW and Nissan to track driver attentiveness while using partially automated driver-assist systems."
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