Associated Press: An alcohol-detection prototype that uses automatic sensors to instantly gauge a driver's fitness has the potential to save thousands of lives, but could be a decade away from everyday use in cars.

Motorists under the influence of drugs are a growing threat on U.S. roads. If you think about driving on a Friday or Saturday evening about 16% of the vehicles - one in six of the cars - the driver will be under the influence of an illicit or licit drug.

"Drugged driving" hampers judgment, reaction time, driving skills and memory.

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16% of motorists may be under the influence of drugs during weekends - one in six of the cars