Court: Ariz. can't suspend driver's licenses due solely to marijuana in blood

Simply driving with marijuana in their system isn’t enough for the state to suspend a person’s license, the Arizona Court of Appeals ruled Wednesday.

The judges rejected arguments by the Motor Vehicle Division that a blood test showing metabolites of the drug was sufficient evidence a driver was “under the influence” of the drug.

Appellate Judge Andrew Jacobs, writing for the unanimous court, said that when voters legalized marijuana for recreational use in 2020, they spelled out in Arizona law that the state may impose penalties on drivers — but only if it can first show the person is “impaired to even the slightest degree by marijuana.”

“But that was not the case here,” he said. “Instead, the state claims it can suspend Kirsten’s privilege of driving for his prior use of marijuana, as evidenced by metabolites of cannabis in his blood, without any impairment.”

In some ways, the ruling is not a surprise. The Arizona Supreme Court in 2014 barred the state from bringing criminal charges of driving while impaired against a medical marijuana user absent proof the person was affected by the drug.

But this case is significant in two ways.

It is believed to be the first appellate court ruling on the issue since voters expanded the legal use of the drug from not just those with a doctor’s recommendation — what was permitted in the 2010 voter-approved medical marijuana law — but to any adult.

And it extends the protections for marijuana users not just against criminal charges but also against administrative suspension of driving privileges by the Motor Vehicle Division, something the agency can do without getting court approval.

According to court records, Sedona police stopped Aaron Kirsten in 2022 for speeding. The officer reported he had bloodshot watery eyes, slurred speech and was unsteady on his feet.

Kirsten refused to take a standardized field sobriety test, though a preliminary blood test showed a blood-alcohol content slightly above the 0.08 that is a presumption for intoxication. But an actual blood draw came back with a level below the limit.

A Department of Public Safety forensic scientist also analyzed the blood for drugs and found some presence of THC, the psychoactive ingredient in marijuana.

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At an administrative hearing, Kirsten testified he had not used marijuana within 24 hours of the traffic stop. He had testimony from a chiropractor and nurse practitioner that THC — or at least the metabolites of the drug, meaning the chemicals caused when the body breaks it down — can stay in a person’s system for weeks.

The hearing officer suspended Kirsten’s driving privileges for 90 days, a decision upheld by Coconino County Superior Court Judge Stacey Lynn Krueger.

But Jacobs pointed to the law voters enacted.

Under that statute, said the appellate judge, Kirsten could be found guilty of driving with metabolites of marijuana in his blood only if there was a finding he was “also impaired to the slightest degree.”

The judges suggested the outcome might have been different had MVD presented any evidence about observations such as slurred speech, but the agency chose instead to rely solely on the blood test results.

“This reinforces our understanding of the voters’ intent, expressed through their enactment of Proposition 207, that unimpaired driving after consuming marijuana cannot be penalized,” Jacobs wrote.

In this case, Jacobs said, the state was seeking to impose a penalty on Kirsten “for reason of his otherwise legal use of marijuana.”

The appellate judge also said the state cannot by law “abrogate or limit any right or privilege conferred or protected by the laws of this state.” And driving, he said, is definitely a privilege.

“The design of Proposition 207 is unambiguous,” Jacobs wrote. “The slightest degree of impairment is required before the state may punish prior marijuana use.”

“Courts must not intrude on the people’s power to legislate,” he wrote, citing prior Supreme Court rulings. He said “voter-enacted laws are even more consequential than those enacted by the Legislature.”