Arizona Rules Zero Tolerance Drug DUI Law Unconstitutional: Could Oklahoma Follow?

Oklahoma has been dubbed one of the "5 Worst States to Get Busted for Pot," largely because of its lengthy minimum sentences and harsh penalties doled out for even minor drug offenses.

Zero Tolerance for Driving Under the Influence

Late last year, the state kicked it up a notch by enacting a zero-tolerance policy for driving under the influence of drugs. Under the law, which took effect on October 1, 2013, a person could be arrested and convicted of DUI if he or she was found to be driving with any detectable amount of marijuana or other Schedule I drug in his or her system. Talk about a buzzkill...

Oklahoma was the third state last year to pass such a law, which enforces "unscientific" per se limits, according to the National Organization for the Reform of Marijuana Laws (NORML). In theory, the idea behind DUI laws is that a person who is impaired by drugs or alcohol is a danger to public safety. However, when it comes to cannaboids and their metabolites, these substances can remain in detectable amounts in a person's blood, urine, or saliva for days or weeks following use-long after the effects of the drug and any impairment have long since subsided.

Carboxy-THC, the metabolite of THC in marijuana, is non-psychoactive-meaning that once the THC breaks down into its metabolite, it no longer affects the individual or impairs a person's ability to drive. Although the lipid-soluble metabolite remains in the bloodstream for a long time after a person smokes or ingests marijuana, it has no effect on the individual.

The National Highway Transportation Safety Administration (NHTSA) itself says of THC metabolites, "It is inadvisable to try and predict effects based on blood THC concentrations alone, and currently impossible to predict specific effects based on THC-COOH concentrations."

Because many states have approved the use of medical marijuana-and two have approved recreational marijuana-a person could theoretically legally smoke marijuana in one state and be arrested for DUI two or three weeks later while traveling through Oklahoma. It seems far-fetched, but it is entirely possible under Oklahoma's zero tolerance law.

However, a recent court ruling in Arizona could (hopefully) have significant implications for Oklahoma's drugged-driving law.

Arizona has had a law since 1990 which classified the presence of inert THC metabolites in a driver's blood or urine as DUI per se. Last month, though, that law was ruled unconstitutional by the Arizona Supreme Court.

In Arizona v. Shilgevorkyan, the state's high court upheld a lower court ruling to dismiss the DUI charge against Hrach Shilgevorkyan, a driver who was charged with DUI after admitting he had "smoked weed" the night before the traffic stop, and a subsequent blood test detected the presence of THC metabolite.

In its ruling, the Arizona Supreme Court found that banning non-intoxicating substances did not follow the intent of the law to prevent impaired driving. Banning all substances, regardless of its ability to impair, is therefore unconstitutional:

"We . . . reject the State's argument that [the law] 'creates a flat ban on the presence of any drug or its metabolite in a person's body while driving or in actual physical control of a vehicle,' even when the only metabolite found is not impairing . . .
Because the legislature intended to prevent impaired driving, we hold that the 'metabolite' reference in [the law] is limited to any of a proscribed substance's metabolites that are capable of causing impairment . . . Drivers cannot be convicted of the . . . offense based merely on the presence of a non-impairing metabolite that may reflect the prior usage of marijuana."

In other words, a person cannot be charged with violating a traffic law simply because of the presence of a non-impairing substance in his or her bloodstream.

In short, the court states, "We are asked to determine whether the phrase 'its metabolite' includes Carboxy-Tetrahydrocannabinol (Carboxy-THC'), a non-impairing metabolite of Cannabis, a proscribed drug listed in § 13-3401. We conclude that it does not."

Prior to this ruling, eleven states plus Washington, D.C., had zero tolerance per se cannabis laws. With its Supreme Court's ruling, Arizona has removed itself from the list. The unconstitutionality of the law in that state should have significant impact on the law in the other ten states which currently have zero tolerance for non-impairing metabolites. When Oklahoma drivers challenge the state's law, our own high court will (hopefully) have little footing to justify upholding the law as constitutional in light of the persuasive precedent set by Arizona v. Shilgevorkyan.

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