As recreational marijuana is increasingly legalized in U.S. states, police departments have been looking for a simple means of identifying if a driver is impaired — something akin to the breathalyzer tests that quickly measure blood alcohol levels, but for cannabis.
One woman says that she has the answer — and detecting people driving while high could be as easy as looking into a camera.
Researcher Denise Valenti created a marijuana “breathalyzer” test — accidentally, she says — while working in an Alzheimer’s research lab. Valenti was trying to find a way to diagnose the early onset of Alzheimer’s using eye exams. Instead, she discovered a two-minute visibility test that she says can measure if someone is high. The result is the only test of its kind, and she patented it in 2015.
Dr. Valenti has worked in the field of impaired driving for a decade and said this test can be brought to court and used by law enforcement officials in an effort to reduce deaths and inaccurate DUI arrests. But her patent isn’t taking off.
“[A lot of people] don’t want me to talk about driving high,” she says.
Valenti’s test, designed to measure the level of visibility a driver has when they are high, is a tablet-based app called IMMAD, an acronym for Impairment Measurement Marijuana and Driving. The test is related to the way that a stoned driver perceives the world visually, and thus measures visual impairment; in other words, the results of the test show how much of the driver’s side windshield are visible to the impaired driver. If too much of the road is not visible given the impairment, the driver would be deemed temporarily legally blind and thus unable to drive safely.
The test currently exists on a tabletop, and consists of a set of rapidly-rotating stripes. A camera tracks the movement of the subject’s retina. Based on this retinal movement, it is able to measure the visual impairment that cannabis consumption causes. Valenti hopes to get some funding in order to convert the test to an app that will use a tablet’s built-in camera for retinal tracking.
Current marijuana blood or saliva tests are inaccurate because THC, the chemical found in cannabis that makes one high, can remain in the bloodstream for several days. In states where marijuana is legal, a driver who has a certain level of THC in their blood can be legally impaired without necessarily being high, according to Jolene Forman, a staff attorney for the Drug Policy Alliance.
The gap between THC levels and actual impairment is one that can’t be bridged, according to most marijuana policy experts such as Forman. For Valenti, it’s a matter of money.
Valenti is looking for $500,000 in funding to roll out the device nationally, which could take 18 months. But the only sizeable offer she’s received was one to shut down her test.
Valenti’s business partner Mark Pomplun, who specializes in the test’s development, say the funding issue lies within their inability to find sponsors who want to invest in a “marijuana-explicit” project in Massachusetts.
“We’re specific to marijuana. And people are afraid [to invest],” Valenti says. “But I see…