Are you ready for your car to decide if you’re fit to drive? If not, you’d better buckle up. A federal mandate declares new vehicles must have in-car surveillance for 2027 models onward that can decide if a person is fit to drive and can make the car inoperable via a so-called “kill switch.” And don’t count on brushing your teeth or gargling with Listerine to work around the driver monitor if you’ve had one too many. Most new cars won’t make the determination via breathalyzer, but infrared cameras continually monitoring potential impairment cues. They include pupil size, head movements,...