driver stopped at a red light keeps looking down at his lap, then up at the road. We’ve all seen it before. And we can probably guess what’s going on.

This stealth driving technique has gained popularity among scofflaws of the state’s hand-free driving law that now is a year old, some police officers say. It makes it harder for police to spot drivers texting, checking emails or dialing their cellphones.

But it’s also pretty risky.

"In my opinion, where people before were holding the phone up on the steering wheel so they could … see what they are doing, now they are holding it on their lap so it is not visible to police, which is more dangerous because now they are looking down at their lap," Nashua Police Officer Sean Mabry said last week.

It’s part of the reason why law-enforcers have mixed reviews about how well the stricter hands-free driving law is working since it took effect July 1, 2015.

On the one hand, police agree the law is easier to enforce. Simply stated, it prohibits anyone from having a mobile device in their hand while driving for any reason except to call emergency services.

In addition, there has been a notable decline in the number of fatal collisions caused by distracted and inattentive motorists in 2015, according to data from the state Department of Safety.

Distracted driving had ranked as the second- or third-leading cause of New Hampshire road deaths for the prior 19 years, said Capt. Matthew Shapiro, highway safety commander for the New Hampshire State Police.

It dropped to sixth place in 2015 and is responsible for just one death – or about 2 percent of the total 55 road deaths through June 19 this year, according to Roberta Emmons, business systems analyst at the Department of Safety.

While the data is too preliminary to draw conclusions, Department of Safety officials say the numbers are promising.

The 2015 data captures not only from the first six months that the law was in effect, but also the prior six months when the state conducted an intensive public information campaign to educate the public about the change.

"It’s only one year of data. However, it would be awful coincidental – after 19 years of distracted driving being the second- or third-most likely cause of fatal crashes – to have it drop all the way down to number six, and that happened after a yearlong publicity program," Shapiro said in a recent interview.

"Even though you can’t hang your hat on it being statistically reliable, it’s promising," he added.

Statewide, drunk, drugged or otherwise impaired driving ranks, by far, as New Hampshire’s leading roadway killer – causing 30-40 percent of deaths in the last 20 years, Shapiro said.

According to state safety department data, inattentive and distracted driving caused: 13 of the 120 road fatalities in 2010 (11 percent); 14 of the 84 deaths in 2011 (17 percent); 10 of the 101 deaths in 2012 (10 percent); 14 of the 124 fatalities in 2013 (12 percent); and 13 of the 89 deaths in 2014 (15 percent).

In 2015, six of the 103 fatal collisions – or 6 percent – were due to distracted or inattentive driving, the state data shows.

None of the five traffic fatalities that occurred in Nashua from July 1, 2014 through last May 19 were caused by distracted driving, Nashua Police Capt. Joseph Fay reported.

Pedestrian error and speed were responsible for the two deaths that occurred from July 1, 2014 through June 30, 2015, he said. The three deaths that occurred from July 1, 2015 through May 19 were caused by speed and a driver making a U-turn, he added.

Mobile device use while driving was "absolutely rampant" from 2010 to 2014 after cellphones essentially evolved into hand-held computers, Shapiro said. Yet the law at the time was "riddled with loopholes," he said, and difficult to enforce because it only prohibited texting and two-handed mobile device use while driving.

State police issued fewer than 100 violations for mobile-device use while driving in 2012, he said.

"It’s not that it wasn’t going on, it (the law) was unenforceable," Shapiro said.

In contrast, state troopers stopped at least 6,091 cars for violating the hands-free driving law from Jan. 1 through June 19 this year, Shapiro said. The stops resulted in 3,215 citations and 2,876 verbal warnings, he added.

"Overall, it has made a big difference with regard to the driving culture in New Hampshire," Shapiro said, speaking anecdotally.

While there are still drivers using cellphones while behind the wheel, there appear to be far fewer than there were four to six years ago when "this was absolutely out of control," he said.

"Even if you did it yourself and you got away with it many, many times and hadn’t hit anything yet, that doesn’t mean that driver isn’t also a pedestrian, a runner, a biker, a dog walker who doesn’t want to get hit by somebody else. You saw this opinion where almost everyone universally agreed it was dangerous," Shapiro added.

Speaking anecdotally, Shapiro noted also that there are a greater number of violations on roadways from Concord and Manchester south to the Massachusetts border in Nashua.

"It seems to occur at a higher rate the farther south you are," Shapiro said. "Is it because it’s closer to the border? Maybe. Is it because there is 10 times more traffic there than north of Concord? I don’t know."

Nashua Police Officer Mabry was less than 15 minutes into a downtown traffic enforcement detail in when he spotted a driver holding her cellphone in front her face while driving north on Main Street last week.

"All day long, it’s not difficult to come up with these – again, blatantly holding the phone right up," Mabry said as he pulled the black Chrysler sedan over near Southern New Hampshire Medical Center.

When he stepped out to speak with the driver, he said he saw her purse on the console with her cellphone sitting on top of it. She admitted she was on the phone.

"She said she was talking to her sister," Mabry said. When a check of the woman’s license and registration revealed no prior violations or warnings, Mabry returned to explain the law to her and gave her a verbal warning.

He said he sees education and deterrence as an important part of his job.

Mabry pulled back into an abandoned service station at Main and Prospect streets where overgrown brush concealed the marked SUV from passing traffic. Minutes later, another driver passed by holding a cellphone in front of his face. Mabry pulled him over in front of the Goodyear Tire and went to talk to him.

"He had it up (in his hand). I explained to him you can’t actually have the phone in your hand while you’re driving," Mabry said. Again, he issued a verbal warning because the driver had no prior violations or warnings on his record.

Minutes later, another driver passed talking on the cellphone, but got lost in traffic before a stop could be made.

Mabry, who did traffic enforcement for three years before being assigned to patrol the Tree Streets, said he has issued six violations since the law took effect. While traffic enforcement no longer is his primary beat, he said he still stops one or two drivers a day for violating the law.

While he says the law makes it easier for police to enforce violations, he said he isn’t convinced the law has made much of a difference.

"It’s hard to say. I still see the same amount of violations," he said.

"I don’t think it’s actually changed people’s driving habits. I’m sure there are … good, law-abiding citizens that do follow it. But, it seems to me that people are actually trying to be more sneaky with it and that may actually be more dangerous," Mabry said, referring to drivers who put their devices on their laps to avoid being stopped.

"This is my opinion. I don’t have raw data to back it up," he noted.

According to Nashua police data, distracted or inattentive driving was a contributing factor in 396 motor vehicle collisions in the 12 months before the new law took effect.

It was a contributing factor in 346 of the collisions that occurred from July 1, 2015 through May 19, police said.

Kathryn Marchocki can be reached at 594-6589, kmarchocki@nashuatelegraph.com or @Tele-graph_KMar.