Too Stoned to Drive?

Colorado's new DUID law treats pot smokers as public menaces even when they're not.

Last week, when the Colorado General Assembly passed groundbreaking legislation aimed at taxing and regulating marijuana, it also passed a bill redefining when cannabis consumers are considered too stoned to drive. The revised rule seems consistent with the voter-approved policy of treating marijuana like alcohol and therefore may be copied by other states that decide to follow Colorado down the path to legalization. But the standard has little scientific basis, and it creates unfair legal risks for people who pose no threat to public safety.

The new law allows a jury to convict someone of driving under the influence of a drug (DUID) based on nothing more than a test indicating that his blood contained five nanograms or more of marijuana's main active ingredient, tetrahydrocannabinol (THC), per milliliter. The Colorado legislature had rejected the five-nanogram cutoff on five other occasions based on concerns that it is a poor measure of impairment.

Those concerns are well-founded, because there is wide variation in how people respond to a given dose of THC. Although some people may be dangerously impaired at five nanograms, regular consumers, including patients who use marijuana as a medicine, can drive competently at much higher THC levels because they develop tolerance to the drug's effects and learn how to compensate for them.

Since THC accumulates in fatty tissue, it can be detected in the blood of frequent users days after their last dose. But that does not mean regular pot smokers can never drive safely.

In a 2012 experiment by KDVR, the Fox station in Denver, a medical marijuana user arrived with a THC level of 21 nanograms per milliliter, even though he had not consumed any cannabis that day. He performed fine on a driving simulator both before and after smoking marijuana, which raised his THC level to 47 nanograms.

This year KIRO, the CBS affiliate in Seattle, enlisted three volunteers—a daily medical marijuana user, a weekend smoker, and an occasional smoker—to navigate a car through a test course under the watchful eyes of a driving instructor and a police drug recognition expert. The volunteers completed the course satisfactorily both before and after smoking various amounts of marijuana, at THC levels ranging from four to seven times as high as five nanograms. The daily user smoked 1.4 grams of pot, reaching a THC level of 58.8 nanograms, before she was clearly too stoned to drive.

Last month Teri Robnett of the Cannabis Patient Action Network told Colorado legislators "patients like me...will continually maintain a blood level far above five nanograms and without any impairment." A five-nanogram standard unjustly exposes people like Robnett to the risk of being treated as a public menace whenever they get behind the wheel.

Suppose Robnett is driving down a highway and briefly drifts from one lane to another before moving back—not because she is stoned but because she is distracted by a wasp that flies into her car. A cop pulls her over, thinking she is driving erratically. It emerges that she consumes marijuana regularly, and a test shows a THC level of 10 nanograms. Under Colorado's new DUID law, it would be understandable if Robnett chose to plead guilty, even though she wasn't. 

Unlike the marijuana legalization initiative approved by Washington voters last fall, Colorado's law does not establish a per se rule, under which a driver is automatically guilty at five nanograms. Instead it creates a presumption of guilt that defendants can try to rebut by presenting evidence that they were not in fact impaired.

In practice, however, there may be little difference between those two standards. With a "permissible inference" of DUID at five nanograms, says Denver attorney Rob Corry, "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."

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  • WomSom||

    Sometimes man you jsut have to roll with it.

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  • Brian D||

    Blunt, but fair.

  • Nazdrakke||

    Sometimes it's all been hashed out already.

  • ||

    I don't get it. I feel like such a dope

  • Rich||

    Put a lid on it already!

  • Spartacus||

    Someone should weed out these silly comments.

  • sarcasmic||

    Nip it in the bud.

  • exchef100||

    Stone the dissenters!

  • natas||

    just don't hit the trees

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  • WTF||

    Sullum argues that the standard has little scientific basis and creates unfair legal risks for people who pose no threat to public safety.

    So, just like the push to lower the DUI standard to .05 for alcohol.

  • Coeus||

  • SugarFree||

    dunphy said that .08 had rock-solid government science to back it up. I guess if Washington state goes to .05 he will refuse to enforce it. Because science.

  • WTF||

    No, he'll just claim that there is new rock-solid government science to back up .05.

  • SugarFree||

    Rock. Solid.

    When they want to push it down to 3 nanograms, that will be rock solid too.

  • Ted S.||

    Nah; Dunphy will be the one gathering evidence about people's alcohol-buying habits without a warrant.

  • ||

    I am friends with my insurance guy, have been long before he went into insurance. Whenever I am near his office I stop in and shoot the shit with him for a bit.

    Once I asked him about the seat belt laws, if fatalities were down since they went into effect. His response; "Cell phones made up the difference."

    Hmmm. In other words, the number of fatalities are unchanged. On the bright side revenue is up.

    Seat belts, impaired driving, inspection stickers, red light cameras, etc etc.....What are the fuckers going to do when driverless cars finally come to pass? I predict much hair pulling and teeth gnashing and that they will fight it tooth and nail. I cant wait to hear their arguments.

  • WTF||

    They will still maintain and enforce seatbelt, DUI, cellphone, etc. laws with tye justification that the passenger must be able tocompetently and safely take control in event of a system failure. That way they can still cite people and collect revenue even though the car is really driving itself.

  • ||

    I had not thought of that, you are probably right. Ugh.

  • ||

    *glances over at 24/7 headlines*

    "Jay Carney Said He Was Sure He Wouldn't Be Any Good As White House Press Secretary in 2006"

    Hmmm. If 'any good' means bald faced lying and using tortured, weasely logic to excuse anything the WH does and cover their asses then he is fantastic at the job.

  • Loki||

    bald faced lying and using tortured, weasely logic to excuse anything the WH does and cover their asses

    Isn't that pretty much taken directly from the job description of "Press Secretary"?

  • Almanian!||

    law treats pot smokers as public menaces even when they're not

    So, pretty much like it's been for - well, way before I was born. Greaat "progress" America!

  • Rich||

    Obviously the solution is to have every vehicle occupant go through a security/impairment/attitude checkpoint before getting onto any major highway. We do this for commercial air travel, which is *much* safer than road travel.

  • ||

    Presumably, like with alcohol, you would only be subject to a test of your blood THC level after you'd been pulled over on suspicion due to your shitty driving. If you so badly suck at driving that you can be easily confused for someone impaired by drugs or alcohol, avoid marijuana, or carefully document what a moron you are in case you wind up in front of a jury. If you can drive without impairment stoned off your ass, how is the cop going to know to target you? I know, I know. The pigs will pull you over for a busted tail light and subject you to a blood test for kicks. Probably true. I'm no cop apologist. But generally speaking, unless a cop just gets a huge woody for you for no particular reason whatsoever, you aren't going to get popped under this law unless you are, in point of fact, driving like a moron - whether due to impairment from marijuana or not.

  • sarcasmic||

    If they pull you over and the car reeks, you're getting blood drawn.

    Don't smoke in the car.

  • Loki||

    DUID checkpoints.

  • ||

    Another definite possibility. I have no idea how DUI checkpoints can possibly withstand constitutional scrutiny.

  • Agile Cyborg||

    I tend to agree with your logic. One of my dear friends spent 20 years as a full-blown alchoholic/pharma/cokehead/pothead but who was never busted while driving because he treated driving like a science- both inside and out. He had it down to a T- in spite of the outrageous stupidity of such activity.

    However, other people will not be as lucky as my buddy. The major concern for a pot smoker in a legal state or a light drinker 'anywhere' will be vehicle breakdowns or involvement in an accident that is the fault of another driver that attracts or requires the attention of police. An anal cop could make life miserable pretty quickly for the clear-headed toker or drinker which is why I despise low blood alcohol limits.

    If pot goes legal nationwide it will be effectively still a prohibited activity for anyone who thinks and drives if the THC thing isn't resolved in a matter that makes sense.

    On another note I'm surprised by the ignorance of most in average society who imbibe one or two drinks at restaurants or bars and drive home. The tremendous legal liability this incurs for a mediocre buzz is astounding.

  • sarcasmic||

    involvement in an accident that is the fault of another driver that attracts or requires the attention of police

    Yep. You can get hit by a car that ran a red light, and if you got a hint of booze on your breath you're getting a DUI and the report will make no mention that the guy who hit you ran a red.

    I know this from personal experience.

  • Agile Cyborg||

    Anymore I rarely drink in public unless all the bases are covered which tends to be a hassle in most instances.

    So, I created my own nightclub here at the house. As a heavy drinker it's a necessity.

  • z80kid||

    Same thing happened to a buddy of mine down in FL. He was under the limit, and had been hit in the side by someone who ran a red light. Naturally, it was all his fault.

  • ||

    That's a fair point for sure, but I don't see it necessarily being as big a problem as the article suggests. By and large the point still stands that if your driving legitimately isn't impaired, you probably won't have anything to worry about. Most of the people who drive at or above the legal level for impairment aren't caught under that system for the same reason. And of course, we're sort of suggesting a false dilemma here to an extent. It's not as if driving stoned is currently legal - there's just no framework for acceptable levels of the drug because there is zero tolerance. This certainly beats that.

  • ||

    *at or above the legal level for impairment for alcohol

  • z80kid||

    They pull you over whenever they want to. Anything will do as an excuse.

    Twice I've heard "Oh-it-looked-like-your-inspection-was- expired-but-I-see-now-that -it's-not-but-since-I-pulled-you-over- I-need-to-see-your-license-and-registration" all in one monotone, well rehearsed breath.

    I have no accidents and no citations in over 20 years of driving. Not once have they found a valid reason for pulling me over.

  • Despiser||

    One way or the other you will be a LAW BREAKER to this corrupt out of control Govt... After all how would we pay retired cops salaries for 30 years if people weren't constantly "breaking the Law"... Reality is not part of the Conversation when the Govt talks Pot.

    Govt is the problem...

    No CONSENT 2013

  • Despiser||

    Lets examine for just one second what has taken place in Colorado shall we. Before the Law what was the punishment for a simple Pot possession? Now that Pot is legal, what will the punishment be for a 502? Which is worse for YOU and better for the Govt and all of the GSEs that suck along for the ride? Why don't people question why all of the insurance companies and Lawyers are owned and operated by PROGRESSIVES that just happen to contribute huge sums to certain Democrat Politicians. Whom employ these same Democrats children and friends in all of the Mgt positions? Move along, nothing to see here...

    NO CONSENT 2013

  • dan'o||

    Perhaps the limit could stand at 5 with possibility to qualify for higher levels based on simulator performance. Though govt would undoubtedly fuck it up and make it painfully expensive, I can't think of anything better...

  • Anders||

    Waiii, whaaaaa? Dude?!

    Colorado banned those evil assault weapons and the big capacity hair clips. They charge new car buyers an elevated registration fee based on the price of their planet-destroying, capitalist scum bag soccer mom breeder baby trains. And Hickenlooper is like, awesome for making weed legal.

    This is harshing my mellow though.

    Maybe I won't move to Colorado after all.

  • joebanana||

    Or visit, or not spend all my money while not vacationing there.

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  • Henry the Twooth||

    Alcohol is the only substance that has a legal limit because it runs through the system relatively cleanly. The same is not the case for MJ. While I understand that desire to have a similar max level, it simply is not scientifically justifiable as in the case of alcohol.

    I would also note that there are hundreds of LEGAL substances that impair driving and do not have mandatory maxima - namely, prescription medicine.

    If driving is impaired, then road side tests should establish that fact.

    Remember, driving recklessly is illegal regardless of whether you are on drugs.

  • joebanana||

    What is "impared"? Sleepy? Pissed? Yelling at the kids? Picking up the babies bottle from the floor for the fifth time? Sneezing? In a big rush? Zanix? Hungry? Paxil? Zoloft? Too much coffee? Mad at the spouse? Cigarette cherry in the crotch? 5ng/ml is the cutoff for the test, and an absurdly minute amount of "imparement". When you can't pass a field sobriety test, then you may be "impared". Cops are going to be having people pissing in a cup along side the freeway. What if you have hay fever? How do you tell if Asain's are "impared"? It's just like Garbage Grove, trying to ban cannabis shops, the law say's CALIFORNIA, it doesn't exempt certain cities G-damn it.

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  • FucktheNannyState||

    God forsaken hippies and their god damn weed.

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