5 Nanogram Marijuana Bullshit

Reason Magazine calls bullshit on CBS4 and their attempt to justify a five nanogram marijuana driving limit in Colorado:


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.

6 Community Comments, Facebook Comments

  1. Tom says:

    My understanding of biology and marijuana is a bit sketchy, but treating THC levels like they do blood alcohol levels doesn't seem realistic unless the idea is simply to find another way to convict majiuana users. THC remains detectable in the blood well after the high has worn off. Since THC is fat soluble and can accumulate in tissues, regular users may always have some level in their blood.

    Will a 5 nanogram limit mean that marijuana users may have to avoid driving for days after they use pot? I don't know the rate THC is metabolized or what 5 nanograms represents in terms of sobriety. Is this an objective test that can be used to determine a person's ability to drive and the limits need to be more realistic? Or is a blood test a measure of an irrelevant proxy and lawmakers need to explore other ways to make sure drivers are safe

    • DaftPunk says:

      This really is the wrong way to test the statute.  No one should be arguing for lighting up and then driving.  My concern is what are the levels in the bloodstream two days after a big high.

      • Gray in Mountains says:

        1 day, indeed the next morning after a night of bonging. 2 days, etc. You're right, not a way to test to arrive at a level. I think this is an area, ala PEDs, where the testing will lag the behavior quite a bit

  2. dippleganger says:

    This is law enforcements way of disenfranchising the would be pot smokers. They know very well that a person who smokes 3/10th of a gram or whatever, what is that? a bowl?…. are not a major threat to the roadways. It's just like the Grand Junction PD telling the citizens it protects, that it is illegal to smoke it on your front porch but ok to smoke it on your back porch. They are hoping that people will just get bothered and scared and choose to not smoke it. 

    Marijuana opponents still consider it a class I drug, just as bad as mushrooms, meth, ecstasy and a plethora of other really nasty chemicals. It's pretty preposterous that they won't stand to reason, or even look at the scientific evidence to counter their deluded beliefs. 

  3. dippleganger says:

    oh and it's not wrong to drive with 5 NANOgrams of THC in your bloodstream. Police only bust you if your driving is  impaired. As the article shows, it doesn't seem like 5 ng will make much difference. Just be a responsible driver and everyone is happy.



  4. Canines says:

    Aurora Sentinel editorializes against marijuana DUID bill:

    EDITORIAL: Driving while high limits nothing but a low point in science and fairness

    The erroneous science behind Fields’ bill could lead to serious consequences for Colorado drivers who really weren’t intoxicated or impaired while driving a car




Leave a Reply

Comment from your Facebook account

You may comment with your Colorado Pols account above (click here to register), or via Facebook below.