You’re driving home one evening after a long day at work when suddenly your Apple Watch massages your wrist to get your attention. You look at your wrist and see it’s just another celebrity update on Twitter. Okay, so those two seconds you took your eyes off the road were a waste of time. Was it a risky thing to do? Probably. Was it against the law? That depends.

There are currently no distracted driving laws specifically addressing smartwatch use in motor vehicles, nor are any brewing, according to Deborah Hersman, president and CEO of the National Safety Council, a consumer-safety organization that focuses on such legislation. “Technology is moving at a much faster clip than our laws can keep up with,” she says.

It's not as though smartwatch-induced distracted driving is a major problem right now—smartwatches don't adorn many wrists yet. But the introduction of the Apple Watch this spring is bringing new attention to the category, as analysts predict consumers will gobble up 28 million smartwatches this year—15 million of them made by Apple.

Even when laws do catch up with smartwatches, enforcing the rules is going to be quite a challenge for police, according to Jeffrey Levine, a New York City-based attorney who specializes in traffic-violation cases. (New York City law-enforcement agencies issue 10,000 cell-phone-related summonses a month.) That's because police can act only on what they can observe.

How does the Apple Watch stack up against other high-tech wearables? Check out our smartwatch comparison page.

“The law expects you to have both hands on the wheel and both eyes on the road,” Levine says. “If you’re holding your phone, a cop knows your hand is off the wheel. And a cop can notice you pick a phone to read a text.”

“Now imagine you’re looking at a text on the smartwatch on your wrist. To a cop it’s going to seem as though you’re checking the time, which is, of course, legal," he says.

Levine, who has handled quite a few horrific accidents in which a mobile device was involved, acknowledges the danger of even quick glances away from the road. “If you're in a car traveling at 50 miles an hour, your car will have moved another 150 feet in the few moments you took to look down at your smartwatch."

In the National Safety Council’s view, that’s only one part of the problem with all laws governing mobile devices in cars. The emphasis on hands-free technology is giving consumers a false sense of security. For instance, 80 percent of drivers polled in a 2014 NSC survey believed that using a hands-free device is safer than using a handheld phone.

“But that’s wrong," Hersman says. “The problem is the cognitive distraction of the brain that causes you to take your mind off the task of driving—not what you do with your hands.”

The organization says at least 30 scientific studies confirm this phenomenon. What’s more, it estimates that 26 percent of car crashes involve some form of cell phone use—talking on a handheld or hands-free device, or texting. Those figures are not likely to improve with a spurt in smartwatch sales.

In one experiment done in the U.K., a driver reading a text on a smartwatch took an average of 2.52 seconds to react to an unexpected event, compared with 0.9 seconds when he was talking to a passenger in the car. His reaction time was 1.35 seconds when he was holding a hands-free phone conversation. He also veered out of his lane four times while using the smartwatch.

“With people in your car, that’s different,” Hersman says. “They’re like your co-pilot because they’re likely to be paying attention to the road as well, and can help spot upcoming hazards.” And even fiddling with the radio or climate controls just don't take as much time, or attention, as talking or texting.

Stay tuned for the results of our tests of the Apple Watch and its leading Android competitors. Among the things we'll be examining is their impact on driving safely.

—Mike Gikas

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