Researchers Developing Marijuana Breathalyzer

With states like Colorado and Washington state legalizing recreational pot, police departments are struggling with the vexing question of how to determine when a motorist is guilty of driving while stoned, according to a recent piece in Jalopnik. Currently, the only ways of determining whether a driver is high on pot is to do a blood test or to do a roadside sobriety test. The former can take up to 24 hours and is often unreliable as it can detect the presence of marijuana in the bloodstream long after a motorist is impaired. The touch your nose and walk a straight line test is also less than reliable for detecting people who are high.

Clearly a marijuana breathalyzer test is needed that will catch people who are too stoned to drive. Some researchers at Washington State University are developing a handheld device that will detect THC, the psychoactive element in marijuana, in the human breath. The pot breathalyzer will be similar to equipment used by the TSA to detect drugs in luggage and on travelers at airport security checkpoints.

The Seattle News Tribune reports that the initial device will not be able to detect the level of THCs, but simply whether it is present. The officer administering the breathalyzer test would still have to order a blood test and use his or her best judgment to determine whether the driver is impaired by pot or not. Researchers intend to start testing the device in early 2015.

The question arises, will the pot breathalyzer be useful in states such as North Carolina where pot smoking is still illegal? If a driver seems obviously impaired but has passed an alcohol breathalyzer test, the next obvious step would be to administer the pot breathalyzer test. The experience in Washington State, where blood samples are regularly tested for motorists who are suspected of driving while high may be illuminating. In 2012, the first year of legal pot, 18.6 percent of blood samples taken from suspected impaired drivers detected the presence of THCs. That number rose to 25 percent in 2013. That data suggests that a working pot breathalyzer will catch more people who might be driving while high, leading to more DWI arrests.

What are your thoughts about a marijuana breathalyzer test? Do you think it’s a good idea to deploy it as soon as possible, or should the states wait until it has been improved to the point where it can detect the actual level or amount of THCs on a person’s breath? 


Image credit: Crime Library