Marijuana and driving: Arizona ruling about inactive THC and Colorado proposal

In a post published earlier today, marijuana attorney Rob Corry argued against a bill to set a THC driving standard, noting, among other things, that pot's markers linger in a user's system far longer than alcohol even when the individual is sober. But the law doesn't always recognize these differences, as seen in an Arizona court ruling. It establishes that people there can be found guilty of driving under the influence whether they're impaired or not.

As noted by Phillip Smith in a post written for his website StopTheDrugWar.org, the Arizona Court of Appeals was asked to weigh in on a case involving Hrach Shilgevorkyan, who was pulled over in December 2010 for speeding and unsafe lane usage. According to the Court of Appeals opinion, issued last week and on view below in its entirety, Shilgevorkyan subsequently consented to a blood test that showed an eight nanogram-per-blood-milliliter concentration of Carboxy-Tetrahyrocannabinol, or Carboxy-THC.

Note that the Colorado proposal related to driving under the influence of drugs would set a five nanogram THC standard.

The deputy who stopped Shilgevorkyan subsequently filed an Arizona traffic ticket charging him with two counts of driving under the influence, referencing a state statute that makes it "unlawful for a person to drive or be in actual physical control of a vehicle" while there is a banned drug or "its metabolite" in its system.

Shilgevorkyan moved to dismiss the complaint, because Carboxy-THC is marijuana's inactive ingredient, as differentiated by Hydroxy-Tetrahyrocannabinol, or Hydroxy-THC, the metabolite that would indicate impairment. As such, he maintained, the presence of Carboxy-THC didn't prove he was impaired.

A superior court judge agreed, in part because of what he saw as ambiguity in the statute over whether the phrase "its metabolite" was singular or plural. After determining singularity made the most sense, the judge ruled that prosecutors hadn't shown "the legislature necessarily intended to include all possible derivatives of drugs -- particularly inactive end products that no longer affect an individual."

Sound logical? Not to the appeals court, which determined that the legislature "intended to create a 'per se prohibition' and a 'flat ban on driving with any proscribed drugs in one's system." Hence, the ban should be applied to "all substances, whether capable of causing impairment or not."

In other words, Shilgevorkyan should have been considered guilty of driving under the influence of drugs even if said drugs didn't actually influence his driving. Catch-22, anyone?

Continue for more about the Arizona ruling, including the complete opinion. By the way, THC-driving bills that narrowly failed in the Colorado legislature during 2011 and 2012 created "per se" limits -- meaning that anyone who tested at five nanograms per milliliter of blood would automatically be considered impaired. The latest version would create a "permissible inference" exception, giving a defendant the opportunity to present evidence to a judge or jury showing that he wasn't actually impaired despite the positive test results.

Attorney Corry doesn't believe this adjustment solves the problem, though. In a previously unpublished excerpt from the interview featured in the earlier post, he suggested that confusion over the different ways the human body processes marijuana versus alcohol make injustice a very real possibility.

"Maybe the average juror doesn't see it our way or is maybe biased going into it," he says. "There are probably already innocent people convicted because juries aren't as predisposed to understanding marijuana as they are alcohol."

His implication? Many Colorado jurors are likely to determine that someone is guilty of driving under the influence whether he or she has active THC in his system or not.

Here's the aforementioned ruling:

Driving Under the Influence of Marijuana: Arizona v. Myra Harris

More from our Marijuana archive: "THC driving bill: Marijuana lawyer Rob Corry suggests a compromise."

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