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Can This Breathalyzer Help Cops Know if Drivers Are Actually High?

The folks at Hound Labs say their device is the future of THC testing.
Photo courtesy of Hound Labs

You know how stoners say they're better drivers when they're stoned? For all anyone knows, that might be the case, since there's still no scientifically proven connection between a certain measurement of THC in your system and dangerous driving. But if such a connection exists, the inventors of the latest roadside THC-detection system are hoping their new doohicky can find it.

Hound Labs is an Oakland-based company founded by Mike Lynn, an ER doctor and reserve deputy sheriff. With his brand-new breathalyzer, Lynn told VICE, "we're able to do what no one else has done, which is to measure breath levels of THC." They also claim it's sensitive enough to detect edibles.


And according to a press release issued by the company, their device is the "first to be tested by law enforcement at the roadside."

Under some current THC driving laws, it's illegal to drive with a certain level of the chemical in your blood, usually 5 nanograms per milliliter, like in Washington. But even the AAA Foundation for Traffic Safety says that that enforcement standard doesn't correspond with impairment. According to Lynn, the 5 nanograms per milliliter amount lingers in the blood long after a person has stopped being an unsafe driver, and CNN's 2013 report on stoned drivers backs that assertion up. "What happens is you get the arrest of people that may have smoked at a party three days ago," said Lynn, calling that state of affairs, "totally unfair, and frankly pointless."

Joe Heanue, CEO and engineer at Triple Ring Technologies, actually developed the new technology, which he says is much more accurate than previous THC tests. "Our challenge is trying to take the sensitivity of a mass spectrometer and put it in a format that could be used by the roadside," Heanue told VICE. Heanue and Lynn say their device will require new legal standards that focus on a breath measurement rather than a blood measurement. "There are laws coming," Lynn said.

"I've heard these stories before," said Dale Gieringer, California state coordinator of the National Organization for the Reform of Marijuana Laws (NORML), pointing to systems like this that have been introduced in the past, but never made it onto any police belts. "They're all the same. None of them [are] going to work," Gieringer added. The trouble, he claims, is that THC in the body isn't as clear-cut of a sign of impairment as it is with alcohol.


Measuring for most drugs in human breath—including THC—is tough, but alcohol and breathalyzers are a match made in heaven. First of all, the familiar range of intoxication levels, and how they correlate to impairment, is pretty uncontroversial. And second of all, the level of alcohol you find in someone's breath and the level of alcohol in their blood are directly correlated, which is not the case with THC. "The relationship between breath THC and blood THC is not linear at all," Lynn explained. "You can't make those inferences."

So he'd prefer to toss out the blood THC standard completely and described breath-THC measurement with his device as "completely different" and in need of a new standard. That means starting from square one: "You go to a track," Lynn said, to "get your drivers high." Researchers will repeatedly measure them with this device and see how that corresponds to performance, and "start to see a range." Only then can you figure out what number corresponds to 0.08 BAC, the point at which you're too drunk to drive.

Lynn has performed some tests but won't hint at the new magic number for THC. "I don't want to hazard a guess at this point," he said. But he said it likely won't be anything even close to the 5 nanograms per milliliter standard. "We're in picograms, which is parts per trillion," he offered—a much more minute measurement.

Gieringer remains doubtful that such testing will pan out, because the connection between THC levels and performance is so vague. He was adamant that, "measuring how much THC is in the brain beyond the blood-brain barrier is pretty much impossible to do from outside the brain." Until peer-reviewed scientific journal articles come along, he called the Hound Labs device "unproven technology."


Lynn, for his part, says independent researchers will be involved. The University of California, San Francisco, he said "will be conducting a rigorous clinical trial, using our device and comparing it to their own gold standard [testing equipment]"—with the intent being "for UCSF to publish this study."

Gieringer claims that any such publication study will be slow going, saying, "I imagine it will be numerous years."

In the meantime, according to Lynn, "We are gathering data. We'll have data that other people can use—law enforcement groups and research groups." He thinks that soon we will all finally know the approximate THC breath levels that mean people are too stoned to drive.

And they'll be levels, he says, that "weren't just pulled out of thin air like blood THC levels."

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