A number of states are testing the machines — Colorado, Kansas, Michigan — and now Massachusetts.
The Patriots game has just ended. There are a lot of cars on the road — prime time for Massachusetts State Police to find potentially high drivers at a roadblock in Holyoke.
"Sometimes it's the eyes — red, pupils not reacting to the light," explained Captain Bruce Hiorns. "Nervous when you shouldn't be. Sweating."
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Troopers are looking for volunteers to help them pilot a roadside drug test. Troopers have promised drivers the results can't be used against them in court. It's for research, and they've gotten a surprising number of volunteers.
A trooper leans over to a volunteer and asks, "What did you say you had tonight?"
"Just marijuana," he answers.
State police gave the NBC Boston Investigators the first look at the federally-funded program. The test is a mouth swab that takes about five minutes to detect drugs like marijuana, methamphetamine and heroin in a driver's saliva. It's a positive or negative; it does not tell police how much of a drug is in a person's system.
"We have people that are shooting up while they're driving," said Lt. Dan Griffin. "We're coming up on cars we think are disabled, and it's people that are overdosing."
Griffin says it's difficult to get high drivers off the road. Right now, the best tool they have is an officer's evaluation of a possibly impaired driver — and federal officials warn high driving could soon outpace drunk driving. From 2010 to 2015, OUI-drug citations are up 225 percent.
"This is happening at all times of the day and it's the innocent people who are getting hurt," said Griffin.
The test is not a slam dunk. With alcohol, it's widely accepted that if you blow a .08, you are impaired, but measuring the effects of specific drugs on different people is more challenging.
Troopers take two samples. One they feed into a machine on site for immediate results. They send the other to an independent lab for confirmation. That lab analysis could tell prosecutors how much the driver allegedly had in their system.
Luis Figueroa, 28, was arrested and charged with OUI after troopers say he tried to turn around and avoid the roadblock. The Springfield man, who volunteered to take the test, told us he smoked two joints on his drive home from work.
We asked him if he ever worried he could hurt someone.
"I only smoke on the way home," he said. "That's it."
Police say it's a common misconception they battle — drivers who think marijuana doesn't affect their reaction time.
We asked if it had any effect on him whatsoever.
"No," he answered.
He nodded when asked if he'd do it again.
State Police hope to collect 200 tests by September and then present their findings to the legislature. Changing state law, however, could take years, according to Griffin.
"Nothing moves quickly, and on something like this, we need to move quickly," he said.
The machines cost about $3,000 each and state police are testing two different companies. Because the machines are expensive, they likely wouldn't be used by troopers roadside, at least in the beginning. It would make more sense, police say, to use them back at the barracks with a trained drug recognition expert after a driver has been arrested.