The Toyota system would involve sensors in the steering wheel that could detect alcohol through the sweat of the driver's hands. The system would stop drunk drivers from operating their vehicles by automatically shutting things down if it detects intoxication. And in case the steering wheel sensors don't detect the elevated blood alcohol content (say, if the driver was wearing gloves), sensors could also detect irregular steering inputs (please define "irregular" for driving enthusiasts), or cameras could even monitor the driver's pupils for signs of lack of focus (maybe they wear their sunglasses at night). If anything seems out of order, the vehicle would slowly come to a halt, hopefully not in the middle of freeway traffic. Better to get the drunk driver off the road, but anytime the car takes over the driving, we wonder whether the problem might actually be compounded.
[Source: Detroit News]