A recent ruling by the Arizona Court of Appeals has set a stricter standard for suspending licenses in marijuana DUI cases. The court now requires the state to prove actual impairment rather than relying solely on the presence of THC metabolites in a driver’s blood to justify a suspension.
Previously, detecting THC in a driver’s system was enough to suspend their license. However, THC metabolites can remain in the bloodstream long after marijuana use, making it difficult to accurately assess impairment. Julie Gunnigle, Legal Director for Arizona NORML, explained that these metabolites can linger for days, weeks, or even months after consumption, complicating DUI cases.
This ruling means that simply testing positive for THC metabolites is no longer enough to automatically suspend driving privileges, Gunnigle said. The court’s decision emphasizes the need to demonstrate impairment at the time of driving, not just evidence of past marijuana use.
The ruling comes after Arizona voters legalized recreational marijuana in 2020 under Proposition 207. Despite the change, law enforcement still faces challenges in detecting marijuana impairment. Unlike alcohol, which can be measured using a breathalyzer, marijuana’s effects are harder to quantify.
It’s not something we can measure the same way, Gunnigle noted. An officer can’t just ask someone to blow into a device to check for marijuana in their system.
Deputy Anthony Pool, who leads the DUI unit for the Pima County Sheriff’s Department, said their approach to marijuana DUIs won’t change much. Officers will continue to rely on field sobriety tests and other signs of impairment to identify drivers under the influence.
We’re focused on making sure we’re distinguishing between consumption and impairment, Pool said. He emphasized that officers are trained to gather clear evidence of impairment before taking action, as Arizona law enforcement currently lacks devices to detect marijuana impairment reliably.
The ruling underscores the importance of proving actual impairment to ensure road safety while respecting the legal rights of drivers. Pool reiterated that the department’s goal remains the same: keeping impaired drivers, regardless of the substance, off the roads.