Arizona High Court Rules on Marijuana DUI law

The presence of non-impairing marijuana compounds in a person’s body isn’t a justification for authorities to prosecute under Arizona’s driving under the influence laws, the state Supreme Court ruled Tuesday in the latest opinion on an issue that several states have grappled with across the nation.

The ruling overturned a state Court of Appeals decision last year that upheld the right of authorities to prosecute pot smokers for DUI even when there is no evidence of impairment.

The Arizona Supreme Court opinion noted that while state statute makes it illegal for a driver to be impaired by marijuana use, the presence of a non-psychoactive compound does not constitute impairment under the law.

The opinion focuses on two chemical compounds in marijuana that show up in blood and urine tests – one that causes impairment and one that stays in the system for weeks but doesn’t cause impairment.

The ruling arises from the case of an Arizona man who was stopped by police for speeding and making unsafe lane changes. The man later acknowledged having smoked marijuana the night before, and a blood test revealed marijuana compounds in his system, however, not the form that causes impairment, according to court records.

He was charged with driving under the influence of a drug and operating a vehicle with the presence of the drug’s metabolite in his system.

The state Supreme Court noted that the language of Arizona’s statute is ambiguous and does not make a distinction between the marijuana metabolite that causes impairment and the one that does not when determining whether criminal charges are warranted. Prosecutors had argued that the statute’s reference to “its metabolite” when referring to drug compounds detected in a driver’s system covers all compounds related to drugs, not just those that cause impairment.

“The state’s interpretation that ‘its metabolite’ includes any byproduct of a drug listed in (Arizona statute) found in a driver’s system leads to absurd results,” the high court panel wrote. “Most notably, this interpretation would create criminal liability regardless of how long the metabolite remains in the driver’s system or whether it has any impairing effect.”

In a dissenting opinion, Justice Ann A. Scott Timmer wrote that the law, as is, helps “enhance detection and prosecution of drugged driving” and should remain unchanged. She suggests any constitutional challenges would be better addressed on a case-by-case basis.

Prosecutors had no immediate comment as they were still reviewing the opinion.

However, Maricopa County Attorney Bill Montgomery has said that the Arizona Legislature had the chance to amend the statute’s language to make it clearer after voters approved medical marijuana use in 2010, but lawmakers did not do so.

Montgomery, therefore, had warned that anyone who used medical marijuana simply shouldn’t drive or they risk facing DUI charges. Tuesday’s Supreme Court opinion removes that threat.

“Obviously we’re very pleased, and we’re very relieved that it’s finally over,” Michael Alarid, III, who represented the man charged in this specific case, said Tuesday. “This does have far-reaching impacts on medical marijuana patients, and it basically corrects an error in the interpretation of the law.”

Twenty-one states and the District of Columbia allow marijuana for medical use, while two states – Washington and Colorado – have legalized the drug for recreational use by adults over 21. Five other states this year adopted laws that allow the use of non-psychoactive marijuana compounds for at least some conditions, such as epilepsy. Some are grappling with the similar issue regarding driving under the influence of marijuana and how the DUI laws should apply.

However, only eight other states have laws that allow a driver to be charged with being under the influence for having even marijuana compounds in their systems that don’t cause impairment, according to the Marijuana Policy Project.

Last year, the Michigan Supreme Court ruled that medical marijuana users aren’t automatically breaking the law if they are caught driving after using the drug. That court found that medical marijuana users should have some protections and that police must show that a driver was actually “under the influence” of the drug – meaning impaired – to seek criminal charges.

(Associated Press writer Gene Johnson contributed to this report from Seattle.)