Could This New Smartphone App Help Prevent Stoned Driving?

By May Wilkerson 07/31/15

The Canary app could be the key to determining if a person is too impaired by pot to drive.

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As more and more states legalize recreational and medical marijuana, policymakers are faced with the challenge of how to measure and regulate stoned driving. While technology to test alcohol on a driver’s blood or breath has been in place for years, marijuana is trickier to detect.

A new app called Canary could be the key to determining if a person is too impaired by pot to drive. Developed by tech guru Marc Silverman and sanctioned by national marijuana advocacy group NORML, the user-friendly app involves four basic tests.

There's a memory challenge where you have to recall six numbers that appear on the screen; a reaction game where you have to quickly identify an icon from a series of images; a time-perception assessment where you have to count off 20 seconds in your head; and a balance test that measures your ability to stand on one foot, using your phone’s accelerometer.

It’s illegal to drive while impaired by any controlled substance in all 50 states. This includes marijuana, but the presence of the drug in driver’s systems been difficult to measure. Testing urine and hair strands has proved unreliable, and obtaining a blood test is unrealistic for every driver pulled over.

“It would be nice to have a tool to be able to quantify and verify that what [officers] are seeing is consistent with cannabis impairment,” said Colorado State Trooper Jerry Sharp. “Everybody has an idea of what drunk is, but we as a society are still working on what we envision as high.”

Many companies, like Colorado-based company Lifeloc, are racing to develop the first marijuana breathalyzer, but not without their fair share of obstacles.

“The primary compound in marijuana that causes impairment is delta-9 [tetrahydrocannabinol],” says Lifeloc CEO Barry Knott. “The good news is, just like alcohol, delta-9 is expelled in your breath if you have it in your system. But delta-9 is exhaled in the breath in much smaller quantities than alcohol vapor, so it’s much more difficult to collect and detect.”

Knott says developing and honing these technologies could take up to a decade.

In the meantime, smartphone apps like Canary could be the most effective tool for regulating stoned driving. Unlike breathalyzers or blood tests, the app doesn’t focus on physical markers of impairment, like levels of THC in your breath, but instead on your actual performance on the roads.

“This tool ideally allows cannabis consumers to take control and identify when they present a traffic-safety risk or when they may be under the influence,” says Paul Armentano, deputy director of NORML. “I believe this is information that all responsible marijuana users will want to know.”

The app is already popular and has been downloaded more than 10,000 times since its launch a few weeks ago. Silverman sees the app as more of a self-regulatory tool. He hopes people will use it to keep themselves and others safe by staying off the road if they’re too high to drive. But it’s not intended for use by police to enforce DUI laws.

“I wouldn’t feel comfortable allowing for law enforcement to use it,” Silverman said.

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May Wilkerson is a writer, comic and Managing Editor @someecards. Co-host of the podcast Crazy; In Bed w/alyssalimp. She is also the top Google result for "insufferable lunatic." Follow this insufferable lunatic on Twitter.