The legalization of marijuana in the state of Washington has had a variety of effects on the culture, the economy, and the law. One of the new challenges that law enforcement officials, citizens, and defense attorneys have faced in the past few years is how to determine what driving under the influence of marijuana looks like and how it can be tested and proven.

Currently, a marijuana DUI statute in Washington dictates that driving with 5 nanograms or more of THC in the bloodstream is unlawful. The only method currently used to test and evaluate the level of THC in the body now is through a blood test, which is often administered if someone fails a sobriety test but passes a breathalyzer and is not found to be drunk. Blood tests, however, are more invasive than breathalyzers and require a warrant.

Developing a Marijuana Breathalyzer

In order to make the process of testing for impairment easier, researchers at Washington State University are working to develop a breathalyzer for marijuana. Assistant chemistry professor Brian Clowers is working on the project with assistants in his lab but says that the product is still a year away from being ready to use in real world scenarios. If successful, the device would most likely be very popular, as there is a growing demand for such technology as police forces struggle to effectively evaluate drug use and impairment.

The researchers say that the device in progress is no bigger than a loaf of bread, which means that it would be small enough for police officers to bring on patrol. Further information about the prototype, however, is being concealed by the researchers until the device is ready for testing.

The lab developing the marijuana breathalyzer is currently looking for participants to take part in a study associated with testing the device. Details are not public, however, their call for participants reveals the process of the rather unique study. Washington State University receives federal funding, so they are not allowed to conduct the study in their own facilities.

“The study will take volunteers — all 21 years or older — and begin with a blood test and a mouth swab to create a baseline. Volunteers will then purchase marijuana — whatever strain they choose from whatever state-licensed retailer they prefer — and smoke it in the privacy of their homes. Researchers will then send taxis to pick them up and bring them to a local hospital to complete a second round of testing and they'll also be encouraged to undergo a field sobriety test conducted by local law enforcement.” The drug testing at Pullman Regional Hospital will be legal. They are currently offering to pay participants $30 for the first hour and $10 for each subsequent hour that the process takes.

Even with an accurate breathalyzer test for THC levels in the blood, data about the correlation between THC and impairment is sorely lacking, due to an absence of reputable research. Certain federal laws under the Controlled Substance Act can prevent meaningful research sponsored by reputable sources, such as universities.