NORTH ANDOVER, Mass. — A Breathalyzer exists to detect whether a driver is drunk, and researchers have created a similar tool to determine whether a driver is under the influence of marijuana.
Jason Wedge, a Drug Recognition Expert (DRE) with the North Andover Police, has spent six years getting impaired drivers off the road. And he said marijuana is one of the hardest drugs to detect.
"I've always said, out of the seven [drug] categories, that marijuana would probably be the more tricky [to detect in drivers] because it affects the individual differently," Wedge said.
"It's definitely a trick drug to call if you don't smell it," he added. "The challenges are walking up to the car [and wondering], ‘How often does this person smoke cannabis?'"
With a new marijuana Breathalyzer tool that researchers at Pitt have developed, officers like Wedge could potentially determine how high a driver is.
"I think this device is going to take away that guessing, so you don't just rely on human observation," said Alex Star, a professor of chemistry at the University of Pittsburgh.
The device is small, portable and created using a 3D printer. Star and his team have worked for three years to improve their marijuana breath test and hope it will revolutionize the way police patrol.
"We were more working on this to make the roads safer than anything else, because any level of impairment is dangerous, not just to the driver but to all of us," said Ervin Sejdic, an associate professor at the University of Pittsburgh's Swanson School of Engineering.
Researchers said they tested the device on one person in Canada, and it was successful. But because marijuana is still illegal at the federal level in the United States, the university has to test the device with a machine -- serving in place of a human -- blowing THC into the Breathalyzer.
Eighteen states have either "zero tolerance" or "per se" laws for drivers using marijuana. There is no legal limit for drivers in Massachusetts or New Hampshire.
"It's cart before the horse here," Julie Gaudreau, an OUI defense attorney in Stoughton, said when we showed her video of the device. "There hasn't been enough research about what impairment by marijuana looks like alone, let alone finding out what level in somebody's system would mean they're impaired."
Gaudreau said any marijuana Breathalyzer is worthless if there's no legal threshold for knowing when someone is too high to drive.
Earlier this year, Boston 25 News requested two years of crime stats from district attorney's offices across Massachusetts. The data revealed a disproportionate amount of OUI drug cases that were dismissed compared to OUI alcohol cases.
>> Why it's so difficult to detect, measure, convict drivers high on marijuana
DRE's have been used in law enforcement for decades. The two-week training process is certified by the National Highway Transportation Safety Administration and includes administering a 12-step assessment that involves interviews, field sobriety tests, and measuring vital signs, including a person's pulse, temperature and blood pressure.
But civil rights advocates argue that DRE's are not medically qualified to determine the level of a driver's impairment.
A Maryland court ruled in 2012 that DRE's are "not sufficiently qualified to render an opinion…[their] testimony is not relevant."
Massachusetts' highest court has not ruled whether DRE's are expert witnesses. That's the trial judge's discretion. Some allow it. Some don't.
Related: SJC rules local police can use observations to make drugged driving arrests
DRE Wedge is interested to see where the Breathalyzer technology goes.
"I think technology is a great tool for us. I think anytime we can, [let's] have a tool that helps us to get it right," Wedge said.
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