You probably know it's against the law in most states to text and drive — but studies suggest that many of us still peek at our smartphones when we're behind the wheel.

This habit, however, contributes to distracted driving. According to the U.S. Department of Transportation, 3,179 people were killed in car crashes involving a distracted driver in 2014.

New York is considering a law that would go beyond what any other state has done to allow police to examine drivers' phones after a crash to determine if the driver was texting at the time of the incident.

The man behind this idea is Ben Lieberman. He lost his 19-year-old son, Evan, after a car crash in the Hudson Valley, north of New York City, in 2011.

"The driver of the car my son was in drifted over the yellow line and collided head-on with an oncoming car," Lieberman says. Evan Lieberman was in the back seat, wearing a seat belt. He suffered massive internal injuries and died a month later.

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Lieberman figured the police would investigate and look at the driver's cellphone. He was surprised when they didn't.

"The driver said he fell asleep at the wheel," Lieberman says. "But when I finally got the cellphone records six agonizing months later, I saw texting throughout the drive and near the collision."

Lieberman eventually got the driver's phone records himself, but he had to file a civil lawsuit to do it.

Ben Lieberman (left) and his son, Evan, who died in a car accident in 2011 when he was 19 years old. Ben Lieberman is behind a bill in New York that allows police to examine drivers' phones at the scene of an accident. (Courtesy of Ben Lieberman)

"There's a huge misunderstanding out there that police will look at phones at a crash, or that they subpoena the phone records afterwards," Lieberman says. "Those are both very huge misconceptions."

Law enforcement can subpoena records from the phone company or ask a judge for a warrant to search the phone itself. Sometimes, police and prosecutors will do that, especially for a major crash with fatalities. But they don't always do it because it takes a lot of money and time for cases that can be hard to prove.

"Oftentimes, drivers aren't willing to admit that they were texting on their cellphone or they were distracted by some other source," says Tom Dingus, director of the Virginia Tech Transportation Institute. "It's just underreported."

Police accident reports say distraction is a factor in less than 20 percent of crashes. But Dingus thinks the real number is much higher. When researchers at Virginia Tech put cameras in cars, they found that distracted drivers account for almost 70 percent of crashes.

"They're looking at a cellphone, they're talking on a handheld phone, they're tuning a radio." Dingus says. "All of those things."

How to Know If a Driver Was Texting

Nearly all states have made it illegal to text and drive. Some, like Utah, Illinois and New Jersey, impose big fines on drivers who get caught. But enforcement can be difficult.

In New York, Lieberman is proposing something that's never been tried before. He wants to build an electronic device that could plug right into a cellphone and tell police whether it was in use at the time of the crash. Lieberman insists it would be designed not to look at sensitive stuff such as personal communications.

The device is called the "textalyzer." Think breathalyzer, but for text messages and other electronic distractions.

"You know, it's not gonna have any embarrassing conversations, any embarrassing pictures. It's just gonna show text in, text out," Lieberman says. "I don't think that you have to surrender all your privacy rights to get this right."

He has been talking to the company Cellebrite about actually building the "textalyzer." An accompanying bill has been introduced in the New York legislature.

But civil liberties advocates have big concerns.

"There are so many ways in which somebody could be using the phone in a car that is not a violation of any laws," says Mariko Hirose, a lawyer with the New York Civil Liberties Union.

For example, the driver might be looking at a map, pulling over to the side of the road to send a text or using voice-activation software. The list goes on.

That's not Hirose's only concern.

"This bill is simply providing a way for law enforcement to get around the privacy protections that apply to a cellphone," Hirose says.

But Dingus says the "textalyzer" is worth a try.

"You're putting other people at risk when you drive and text, or drive and check stocks," Dingus says. "It's not just your privacy. You're putting other people at risk."

Maybe the threat of getting caught will help convince more drivers to put down their phones.

Copyright 2016 NPR. To see more, visit http://www.npr.org/.

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