Arizona Supreme Court Makes It Harder to Convict Unimpaired Pot Smokers of Driving Under the Influence

Yesterday the Arizona Supreme Court ruled that people whose blood contains a secondary, inactive byproduct of marijuana can drive without violating state law. That means cannabis consumers are less likely to be charged with driving under the influence of a drug (DUID) when they are not actually impaired.

Arizona, one of seven states with a "zero tolerance" DUID law, forbids driving by anyone whose body contains any amount of an illegal drug "or its metabolite." The question for the Arizona Supreme Court was whether "its metabolite" includes carboxy-THC, which is not psychoactive and can be detected up to a month after consumption of cannabis. The court deemed the phrase ambiguous, since it could be understood as referring only to hydroxy-THC, a primary metabolite that is psychoactive. In light of the legislature's aim to prevent impaired driving, the court said, that interpretation makes more sense, especially since the alternative, including any chemical trace left by the metabolism of an illegal drug, would lead to "absurd results":

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. For example, at oral argument the State acknowledged that, under its reading of the statute, if a metabolite could be detected five years after ingesting a proscribed drug, a driver who tested positive for trace elements of a non-impairing substance could be prosecuted.

The broader interpretation would therefore "criminalize otherwise legal conduct": medical use of cannabis permitted by state law. "Because Carboxy-THC can remain in the body for as many as twenty-eight to thirty days after ingestion," the court noted, "the State's position suggests that a medical-marijuana user could face prosecution for driving any time nearly a month after they had legally ingested marijuana."

The court noted that a broad reading of "its metabolite" could have absurd results when applied to other drugs as well:

This interpretation would allow the prosecution of an individual who drives after ingesting a legal substance that shares a non-impairing metabolite with a proscribed substance. For example, serotonin, a legal substance, and the proscribed drug bufotenine [a psychedelic found in fly agaric mushrooms and the skin of certain toads] share a common metabolite, 5-hydroxindoleactic acid ("5-HIAA")....Under the State's interpretation of "metabolite," it could prosecute a driver who had 5-HIAA in his or her system after ingesting a legal serotonin supplement or, for that matter, whose blood contains 5-HIAA as a byproduct of naturally produced serotonin.

This decision is reminiscent of a 2010 ruling in which the Michigan Supreme Court narrowly interpreted that state's zero-tolerance DUID law, which says a person may not drive "if the person has in his or her body any amount of a controlled substance listed in schedule 1," which includes marijuana, THC, and "their derivatives." The Michigan Supreme Court said carboxy-THC does not count as a "derivative."

Despite these rulings, it is still possible for unimpaired marijuana consumers to be convicted of DUID in Arizona and Michigan, since any amount of active THC in the blood will suffice. In fact, such convictions are possible even under less strict per se standards, such as Washington's new rule equating five nanograms of THC per milliliter of blood with impairment, which makes it illegal for many medical users to drive even when they are perfectly capable of doing so safely. Given variation in the way people respond to psychoactive substances (including alcohol) , per se standards are bound to unfairly tar some people as public menaces That is a good reason to require additional proof of impairment—unless you are using road safety as an excuse to punish people for consuming politically incorrect drugs, in which case per se (and ideally zero tolerance) is the way to go.

[Thanks to Marc Sandhaus and Richard Cowan for the tip.]

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  • Paul.||

    In fact, such convictions are possible even under less strict per se standards, such as Washington's new rule equating five nanograms of THC per milliliter of blood with impairment, which makes it illegal for many medical users to drive even when they are perfectly capable of doing so safely.

    This is what freedom looks like in 2014.

  • Almanian!||

    ....as long as you ask permission and follow orders. What's not to like?

  • R C Dean||

    Good result.

    When the Revolution comes, I'll uptwinkle the proposal that the AZ Supreme Court judges go up against the wall last, rather than first.

  • Paul.||

    "uptwinkle"... I like your style.

  • Hugh Akston||

    It's very unlikely that they'll survive the liberation of Maricopa County long enough for that determination to be made.

  • AlmightyJB||

    You a funny guy. I kill you last.

  • Dweebston||

    Of course, it's impossible to predicate arrests on the grounds of actual symptoms of impairment. No, cops need "bright lines" and all that.

  • Paul.||

    Like the 'Stop Resisting' bright line?

  • AlmightyJB||

    Yeah. Theres an idea. If your driving recklessly, charge you with reckless driving. If your speeding, charge you with speeding.

  • Agammamon||

    Arizona Supreme Court Makes It Harder to Convict Unimpaired Pot Smokers of Driving Under the Influence

    OK, while I want to cheer for AZ here, its only a matter of (a short) time before our legislature does something completely boneheaded. One step forward, 3/4 of a step back.

  • bassjoe||

    After reviewing this opinion, I can't see how the AZ Supreme Court will allow the criminalization of carboxy-THC in the bloodstream even if the legislature specifically targets it...

  • Agammamon||

    I mean next week they'll declare that anyone who looks vaguely Mexican will have to report for 'processinig' or that tittie-bars are ok only as long as the patrons are separated by an opaque wall from the performers or some stupid shit like that.

  • RishJoMo||

    Wow man that is pretty cool. WOw.

    www.GotsDatAnon.tk

  • BigT||

    forbids driving by anyone whose body contains any amount of an illegal drug "or its metabolite."
    A metabolite is any substance produced during metabolism (digestion or other bodily chemical processes).

    The term metabolite may also refer to the product that remains after a drug is broken down (metabolized) by the body.

    I believe that the ultimate metabolites of most things we ingest are CO2 and H2O. Thus, everyone is guilty at all times.

  • bassjoe||

    Don't forget sulphur compounds!

    /always guilty of having those...

  • Rich||

    Thus, everyone is guilty at all times.

    It's THE LAW, enacted by Top. Men.

  • ||

    Thus, everyone is guilty at all times.

    So the Doctrine of the Original Sin is right after all?

  • Agammamon||

    Not really - CO2 and H2O are mainly metabolites of ATP.

    There are tons of stuff the body metabolizes that are used for things other than energy production and/or do not produce CO2 or H2O as metabolites.

    Of course the law is poorly written - it should specify that the metabolites in question are those that are unique to the banned substance or at least have no 'legitimate' source.

    Then this issue would never had popped up in the first place. But really, can you expect a legislature to actually know how and take the time to carefully craft laws to be specificg

  • ||

    the metabolites in question are those that are unique to the banned substance

    I think the issue was that carboxy-THC -- although unique to the banned substance -- is

    - a metabolite with a long half-life
    - non-psychoactive

    and as such its presence in the bloodstream isn't indicative of impairment at the time of driving.

  • ||

    OT: I've just seen a serial tree hugger! I was out on my balcony and spied this dude hugging a scrawny tree; then he went on to hug another two.

    His MO: walks up to the tree, hugs it with left foot on the left of the trunk and right foot on the right, forward around two feet of his left foot, head slightly bent on the left of the trunk, then stand motionless for about 5-7 seconds.

  • Cridmosaures||

    If your driving recklessly, charge you
    with reckless driving. If your speeding,
    charge you with speeding.

    Should law enforcement be able to charge drunk drivers before they're reckless or speedy?

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