Colorado Legislators Should Reject an Arbitrary Standard for Driving While Stoned



This week Colorado's House Judiciary Committee, keen to protect the public from newly legal pot smokers who might get behind the wheel after one puff too many, unanimously approved a bill that would allow convictions for driving under the influence of drugs (DUID) based on nothing more than blood tests indicating a THC level of five nanograms per milliliter or higher. Unlike a per se standard, which the state legislature has rejected twice before, the bill would not make people automatically guilty of DUID at five nanograms; instead that would be a "permissible inference." Defendants could avoid conviction by presenting evidence that they were not in fact impaired. Although that approach is better than a per se rule, the five-nangogram cutoff remains arbitrary. It is not supported by scientific evidence showing that people generally are impaired at that level, and tests suggest that many marijuana consumers drive competently at THC levels far above five nanograms. A few weeks ago, I described one such experiment, conducted by KIRO-TV, the CBS affiliate in Seattle, where drivers are subject to a five-nanogram per se standard as a result of I-502, the ballot initiative that legalized marijuana in Washington. Summarizing the results, KIRO's reporter noted that "our volunteers were able to smoke pot and drive safely at four times the legal limit." 

In the hands of KCNC-TV, the CBS affiliate in Denver (a.k.a. CBS4), this striking refutation of the idea that five nanograms is equivalent to impairment somehow became an argument for rushing to establish an unvalidated standard. A CBS4 report that aired two days ago egregiously misrepresents the KIRO study, failing to note that all of the subjects successfully completed a driving course at THC levels much higher than five nanograms. They were also observed by a "drug recognition expert" from the Thurston County Sheriff's Office, who said he saw no reason to pull any of them over after their first round of pot smoking. After smoking repeatedly, all three eventually became too stoned to drive, but their blood test results at that point were nowhere near five nanograms.

CBS4 concedes that one volunteer, Jeff Underberg, "drove very cautiously" with a THC level four times the legal limit after smoking his first three-tenths of a gram. "While his driving was slow," KIRO reported, "it was still acceptable." According to the driving instructor who accompanied Underberg, "He did real well." But CBS4 inaccurately portrays the performance of the other two subjects. The heaviest cannabis consumer, a medical marijuana user named Addy Norton, did not fail the driving test until after consuming a total of 1.4 grams of pot and achieving a THC level of 58.8 nanograms, almost 12 times Washington's legal limit. Yet CBS4 shows her giggling at the wheel and knocking over a traffic cone, implying that she was impaired throughout the experiment. Another subject, Dylan Evans, smoked three-tenths of a gram, reaching a THC level of 26 nanograms, but still was "doing fine behind the wheel," according to the KIRO report. CBS4 falsely claims that Evans "drove off the course" at this stage, adding that "at one point the driving instructor had to grab the wheel," which did not happen until after the third round of pot smoking.

The impression left by the CBS4 story is so misleading that after watching it Westword blogger Michael Roberts, no fan of the five-nanogram standard, wrote that "the KIRO report shows three volunteers who smoke, then climb into vehicles and attempt to navigate a driving course—and mostly fail badly, by either going far too slow or swerving into cones set up to simulate roadways." In fact, all three subjects performed well after their first round of smoking, providing further evidence that the DUID bill moving through the Colorado legislature is based on a mistaken premise.

Rob Corry, a Denver attorney and marijuana activist, argues that a five-nanogram cutoff "completely ignores all the science," which indicates that "there is no particular number that determines impairment by THC across the population. THC affects everybody differently. There are many people who are not impaired at well over five nanograms, and there are some who are probably impaired at under five nanograms." Under current Colorado law, the burden is on the prosecution to show that a driver was under the influence. Blood test results are one kind of evidence prosecutors can use, along with clues like erratic driving and poor performance on roadside sobriety tests, but they are not conclusive. In a recent letter to legislators that Roberts quotes, Corry describes a client who tested at 10 nanograms but was nevertheless acquitted because the evidence showed he was "perfectly sober, driving well, and not a danger to anyone on the road that night." If the law is changed so that DUID is a "permissible inference" from a THC level of five nanograms or more, such defendants will stilll be able to argue that they were not impaired, but that case will be harder to make. "What it does is shift the burden of proof," Corry tells me. "A person coming into court is guilty until proven innocent….If you put a number on it, juries are going to latch onto that five-nanogram number, whether it's a permissible inference or a per se [standard], and the effect will be that innocent people are convicted, whether or not they're impaired." 

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  1. Defendants could avoid conviction by presenting evidence that they were not in fact impaired.

    How exactly do you do that? What counts as evidence that you were not impaired?

    1. Not only is there no way to do that, but as noted in the article, you are guilty until proven innocent.

      It seems to me, a legal ignoramus, that on those two premises the law could be invalidated.

      1. While SCOTUS is no stranger to conjuring rights out of the aether, there is no specific mention of the presumption of innocence in the Constitution.

        1. Not specific, but 5th A. due process would apply.

          1. not relevant to per se standards, etc. for obvious reasons.

      2. I retract my previous post. It was based on principle. I really am an ignoramus sometimes.

        The reality is that our legal system has strayed far afield from the principles it is supposed to embody. In so many ways. It is a travesty.

        I would be very surprised if this law were struck down instead of being applied with an iron fist.

    2. I would say the fact that I hadn’t hit anyone or caused any damage was evidence that I wasn’t impaired.

    3. Numerous way people present such evidence, RC. Witnesses, for example, can be presented as evidence. If the person just left the bar, their CC tab can be used (showing they only bought one drink). Stuff like that I’ve seen before in court.

  2. Defendants could avoid conviction by presenting evidence that they were not in fact impaired.

    “Ladies and gentlemen of the jury, I will now blaze much in the same way as the day in question, and then do this jigsaw puzzle without jamming any of the wrong pieces together. Observe…”

    1. Giggling at my desk…

      …people looking at me.

  3. OT: Our favourite faux-feminist self-loathing male blogger now cites evidence that the key to a happy heterosexual relationship is for the female to fuck the male in the ass. (But no, he’s completely secure in his own orientation and gender identity. No issues there at all, nope.)

    1. I bet if a guy wanted to fuck her in the ass, she’d write a blog post about how men just want to degrade women and use them as sexual objects.

        1. Maybe if I learned to read, I would have seen that. Doh. Sorry, I has the derp today.

    2. Now this, I believe to some extent:

      “For men who have never been on the receiving side of penetration, sex is something that happens outside the body. And when sex is external to your body, it can be easier to do when you have a headache or you’re not quite in the mood. A lot of men discover than when sex is about catching rather than pitching, their mood, their emotions, and their connection to a partner can often have a bigger influence on what they want to do and how it feels.”

      But overall I laughed my ass off at the whole post.

      1. There’s definitely a psychological difference in the way men and women experience sex, but something tells me that if you stick something up ANYONE’s butt when they don’t want you to, it’s not going to make them more receptive to your views on sex.

        1. I don’t think he was suggesting that it be a surprise.

          1. No, but he is suggesting that men that don’t want to are closed minded and fearful of their sexuality. And it’s explicitly stated that it will make men more comfortable in their sexuality.

            If a guy is into pegging, good for him. I just doubt the efficacy of pegging a guy to make him more “thoughtful”

      2. I see the point, but driving the wrong way down a one way street is never a good idea.

        Hugo is a fucking head case.

        1. Oh Hugo is most definitely a head case.

      3. Whatever nicole. You should always be grateful when a guy wants to have sex at you.

        1. Like I’m not! Do you even know me? I am a total whore.

          1. Bring back nicole can’t even!

            She is missed.

            1. She is here with you always, deified.

  4. Alcohol has a per se standard. I thought pot was supposed to be regulated like alcohol.

    1. There is also a question of whether alcohol should have a per se standard.

      1. A question no one in power is asking.

        1. I’ve seen several different ways defendants present evidence they were not impaired.

          However, in WA it’s largely irrelevant at a .08 or above since it is illegal to drive impaired or at a .08. Iow, it is a crime (DUI) to drive with a BAC of .08. One does not have to prove impairment if one proves .08. Granted, most judges ime don’t care, ignore the law, and want to see evidence of impairment, but technically under the law it is a crime to drive with a BAC of .08 or above, regardless of whether it resulted in impairment.

  5. Dude I been smoking pot 3 to 5 times day, every day,. for the last 30 years and have not had so much as a traffic ticket!

  6. It’s remarkable to me that CO is having a discussion amongst citizens, police, and legislators about not how long to lock up everyone ever found on the roads while remotely high but rather exactly how much weed one can smoke in front of a “drug recognition expert” from the fucking sheriff’s office and then proceed to get in a car and drive.

    Sure, sure, legalize all of it everywhere, etc. But in the actually-existing US (excluding California, our nation’s perpetual asterisk), this is pretty amazing progress.

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