Ruling: Medical pot can lead to DUI, even if driver isn’t impaired

A medical marijuana card is not a get-out-of-jail-free card for motorists found with active components of the drug in their system, no matter how little, the state Court of Appeals ruled Tuesday.

The judges rejected arguments by the attorney for Travis Darrah that the positive drug test, by itself, cannot be used to convict him of driving under the influence of drugs. The judges said prosecutors need not prove actual impairment.

Tuesday’s ruling is unlikely to be the last word. Attorney John Tatz said he may seek Supreme Court review, saying the decision is in direct contradiction to the 2010 voter-approved Arizona Medical Marijuana Act.

That’s also the assessment of Chris Lindsey, a legislative analyst with the Marijuana Policy Project which crafted the law.

Darrah, who has a state-issued card allowing him to obtain and use marijuana, was arrested by Mesa police in 2011. He was charged with two separate counts of driving under the influence of drugs.

One makes it illegal to drive while impaired.

The other says a person cannot operate a motor vehicle while there is any illegal drug or its metabolite in his or her body. That was based on a blood test which showed evidence of an active component of marijuana. Tatz asked for the second count to be dismissed.

He acknowledged that the 2010 law does not make it legal for a medical marijuana cardholder to operate a motor vehicle while under the influence of the drug.

But Tatz pointed out the law also says medical marijuana users cannot be considered under the influence solely because of the presence of metabolites or components of the marijuana “that appear in insufficient concentration to cause impairment.” And he said there was no evidence presented that Darrah was not impaired.

The judge refused to drop the charge and refused to let jurors hear that Darrah is a medical marijuana user. Jurors then found Darrah innocent of the impairment charge but, based solely on the blood test, guilty of the second charge.

Appellate Judge Michael Brown, writing for the court, said he does not read the law – and the exemption – as broadly as Tatz.

“If Arizona voters had intended to completely bar the state form prosecuting authorized marijuana users under (this section of the law), they could have easily done so by using specific language to that effect,” Brown wrote.

Lindsey said all that ignores the intent of the law: to allow patients to use the drug and not be kept from driving simply because there was something left in their bodies that shows up in a blood test.

The key, he said, is impairment – or the lack thereof.

“You could have a small amount of active metabolite in the system and not be impaired,” he said, much as someone using a prescription painkiller would not be breaking the law if the concentration was too low to cause impairment. And Lindsey said the 2010 law was crafted to include the impairment requirement because of how long marijuana remains in the system.

Tatz said there is precedent for that argument.

He said the parallel charge for alcohol to the one his client was convicted is operating a motor vehicle with a blood-alcohol content of 0.08.

If the blood test returns a number below that, that charge is dismissed. But the motorist still can be charged with driving while impaired if there is other evidence.

In this case, Tatz said, there is no presumptive number in Arizona law for how much marijuana someone can have in the blood. So that, he said, leaves prosecutors only the option of charging Darrah with driving while impaired – a charge for which his client was found innocent by a jury.

Brown also said this case is different than one where the Arizona Supreme Court earlier this year voided driving while intoxicated charges against another medical marijuana user.

In that case, though, the justices pointed out that what was found in that driver’s blood was an inactive metabolite of the drug which can remain long after the effects had worn off.