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Transportation Technology

With Pot Legal, Scientists Study Detection of Impaired Drivers 608

Hugh Pickens writes "A recent assessment by the National Highway Traffic Safety Administration, based on random roadside checks, found that 16.3% of all drivers nationwide at night were on various legal and illegal impairing drugs, half them high on marijuana. Now AP reports that with marijuana soon legal under state laws in Washington and Colorado, setting a standard comparable to blood-alcohol limits has sparked intense disagreement. Unlike portable breath tests for alcohol, there's no easily available way to determine whether someone is impaired from recent pot use. If scientists can't tell someone how much marijuana it will take for him or her to test over the threshold, how is the average pot user supposed to know? 'We've had decades of studies and experience with alcohol,' says Washington State Patrol spokesman Dan Coon. 'Marijuana is new, so it's going to take some time to figure out how the courts and prosecutors are going to handle it.' Driving within three hours of smoking pot is associated with a near doubling of the risk of fatal crashes. However, THC can remain in blood and saliva for highly variable times after the last use of the drug. Although the marijuana 'high' only lasts three to five hours, studies of heavy users in a locked hospital ward showed THC can be detected in the blood up to a week after they are abstinent, and the outer limit of detection time in saliva tests is not known. 'A lot of effort has gone into the study of drugged driving and marijuana, because that is the most prevalent drug, but we are not nearly to the point where we are with alcohol,' says Jeffrey P. Michael, the National Highway Traffic Safety Administration's impaired-driving director. 'We don't know what level of marijuana impairs a driver.'"
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With Pot Legal, Scientists Study Detection of Impaired Drivers

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  • by Anonymous Coward on Wednesday November 21, 2012 @09:17AM (#42054021)

    You just do the same thing that cops do when the driver refuses the breath test... a Field Sobriety Test.

  • Make the limit 0 (Score:1, Insightful)

    by Anonymous Coward on Wednesday November 21, 2012 @09:18AM (#42054031)

    Make it zero tolerance. If someone is pulled over they are not going to get the test administered unless they are suspected of impaired driving.

  • by Anonymous Coward on Wednesday November 21, 2012 @09:21AM (#42054051)

    What level of marijuana impairs a driver?!? Weed gets you high. There is only one level of high, and that is high. You can smoke 100 joints an hour and still be at the level of high. You drink 100 beers an hour and you will be at the level of dead. There is NO comparison.

  • by Cenan ( 1892902 ) on Wednesday November 21, 2012 @09:42AM (#42054229)

    Who cares? If you for whatever reason aren't capable of driving a vehicle, then you shouldn't be allowed to, no matter the reason. Design the test in such a way that it tests for skills needed to drive a vehicle, kind of like a field driver's exam. Then stop worrying about how much pot is too much and start concentrating on what skills are actually needed to drive. Problem solved.

  • by Anonymous Coward on Wednesday November 21, 2012 @09:43AM (#42054239)

    If they're in a normal state for them and they're still failing an impairment test, then they quite simply shouldn't be allowed to drive. If your reactions are normally that bad, or your perception is that inadequate, you're a danger to other people on the road. Sucks to be you, but it'll reduce the number of accidents on the road.

  • Nonsense (Score:3, Insightful)

    by betterunixthanunix ( 980855 ) on Wednesday November 21, 2012 @09:45AM (#42054259)
    "Looks like a black guy is driving. Let's test him for THC and arrest him if he tests above 0."
  • by damn_registrars ( 1103043 ) <damn.registrars@gmail.com> on Wednesday November 21, 2012 @09:53AM (#42054333) Homepage Journal
    Every time I've been in a discussion on pot here on slashdot, this is what I have asked for - a standard and reproducible test for when someone has consumed too much. Strangely enough, it causes the pro-pot people to call me a fascist and the anti-drug people to call me a druggie.

    I'm glad to know that there is so much room for a middle ground in slashdot political discussion...
  • by Endo13 ( 1000782 ) on Wednesday November 21, 2012 @10:14AM (#42054579)

    All three of these responses are spot-on. Remember, driving is a privilege, not a right.

  • Re:Easy (Score:5, Insightful)

    by rgbatduke ( 1231380 ) <rgb@ph y . d u k e.edu> on Wednesday November 21, 2012 @10:16AM (#42054607) Homepage

    A mere 80 or so years too late, of course. But better late than never.

    Now if any state had the testicular fortitude to challenge them over their utterly unconstitutional use of the threat of withholding federal highway funds from states that failed to raise the drinking age to 21, we might see a restoration of sanity in that direction as well. Otherwise we might as well just ditch the constitution and abolish state and local government and get it all over with.

    But getting the US government out of the marijuana game as the first step to getting it largely out of the drug game altogether might be good first steps to dismantling the current police state, and in the process saving perhaps 100 billion dollars (in all costs) nationwide. Maybe more -- drugs are roughly a half-trillion dollar business globally, and laundering drug money is a major mainstay of our banking system and creates a veritable shadow government with a steady stream of untaxed, illegal income that produces compounded wealth and disproportionate power for those that are involved.

    It also opens up the states that legalize it to entirely new (taxable, now legitimate) industries -- not just recreational pot but an entire spectrum of hemp-derived products that are difficult to impossible to produce at this time. The hemp plant was enormously useful before it was made illegal, and to some extent was made illegal because it was so useful. I wish NC would follow in CO and WA's footsteps, because hemp would make an ideal cash crop to replace tobacco (the real "killer drug" of the US).


  • Re:Nonsense (Score:4, Insightful)

    by dintech ( 998802 ) on Wednesday November 21, 2012 @10:19AM (#42054633)
    OK fine, lets just allow people to drive under the influence of whatever they like and as much as they like. Problem solved?
  • by Anonymous Coward on Wednesday November 21, 2012 @10:24AM (#42054681)

    "Saliva testing only shows up marijuana usage in the last four to five hours, but 24 hours for all the other drugs, including amphetamines (speed), opiates (heroin, morphine, codeine), cocaine, benzodiazepine (valium and so on) and THC (cannabis). The advantages of saliva over urine testing are the speed of obtaining results (10 minutes versus several days) and it is less invasive.

    http://www.druginfo.adf.org.au/fact-sheets/the-facts-about-roadside-drug-testing-web-fact-sheet [adf.org.au]

    So it only shows pot usage for the past 5 hours, but it shows the THC from cannabis for 24 hours? That's certainly a legit "fact sheet"....

  • by Cenan ( 1892902 ) on Wednesday November 21, 2012 @10:26AM (#42054705)

    Yes i have driven around much lately, although not on a US road. But your post underlines my point really. If you are not capable of driving the vehicle you're in, then you should not be allowed to. I don't care if it is because you're 90 and have forgotten how to, or you're drunk of your ass.

    I completely agree with you that there are other problems in traffic than what can be caught on a field administered test, but that is what the patrol cars are for. All I'm saying is don't go after the people high as kites only, target everyone not capable of driving.

  • Re:Well... (Score:2, Insightful)

    by tehcyder ( 746570 ) on Wednesday November 21, 2012 @10:33AM (#42054767) Journal

    My first time wasn't like that. My roommate however, gets that every time.

    Maybe you puritans should just not use it instead of trying to prevent me from using what for me is a working anti-depressant.

    Everyone's different. Live with it.

    There are few people more annoying than those who try to justify recreational drug use with claimed self-medication benefits. Just admit you like getting stoned. I don't kid myself that getting drunk is some serious health exercise, I just enjoy it. Back on topic, I am also anti-drink driving and think this should apply to any drug use (legal or illegal) too. I don't care if you think you drive better with six beers or a couple of joints under your belt. You almost certainly can't, and if you can, tough shit, rules apply to everybody.

  • Re:Nonsense (Score:4, Insightful)

    by Golddess ( 1361003 ) on Wednesday November 21, 2012 @10:37AM (#42054813)

    Problem solved?

    Yes actually.

    You seem to be under the assumption that if we don't test specifically for Drug A, Drug B, Drug C, etc, we are somehow giving people permission to drive while impaired by those drugs. And I cannot see how that is the case. Can't cops still pull you over and charge you with "driving erratically" or whatever they call it when you can't stay in your lane, roll through stop signs, ignore traffic lights, etc?

  • by MakerDusk ( 2712435 ) on Wednesday November 21, 2012 @10:49AM (#42054951)
    If you can balance and judge distances properly, you deserve to pass the test anyways. Since you would not be a danger to other drivers or yourself anyways. In that case it's not a catch all type test, but a catch the ones that can't be driving. One beer might leave a lightweight too drunk to drive, but the same beer wouldn't effect someone else in the slightest. Why punish both if you can distinguish between the one that's fine and the one that isn't.
  • by admdrew ( 782761 ) on Wednesday November 21, 2012 @10:52AM (#42055009) Homepage

    What if you're tired? If you've taken no drugs, but worked twenty hours in a row? You WILL fail an impairment test. But you've done nothing wrong. Maybe you shouldn't be driving.

    Regardless of the circumstances, we have a personal responsibility to not put others in danger with our actions. Vehicles are multi-thousand pound missiles, heavy machinery easily capable of severely injuring and killing other people; if you're too tired to operate one safely, there's really no excuse for doing so.

    Driving is entirely a convenience, and certainly not a right or a requirement. A responsible adult can (and should) plan around the reality of not being able to drive; 'working 20 hours' isn't an excuse, it's a situation that you're dealt with and need to handle, and driving while being tired enough to be impaired is a personal choice.

  • Re:Easy (Score:5, Insightful)

    by CohibaVancouver ( 864662 ) on Wednesday November 21, 2012 @10:56AM (#42055051)

    Decriminalization removes criminal penalties, like jail and record keeping of you being convicted of having drugs. It can still be illegal, but just a minor fine or penalty. Legalization removes all legal penalties.

    Perhaps more importantly, legalization provides a framework for the legal *sale* of weed, in the same way booze has a legal framework for its sale. You don't get that with decriminalization.

  • by Hatta ( 162192 ) on Wednesday November 21, 2012 @10:58AM (#42055093) Journal

    What the hell are you talking about? There's decades of research on impairment caused by cannabis. We've been fighting a war on the drug for decades, and the prohibitionists have been looking for any possible harm they could blame it for. There's lots of research out there on how Cannabis affects driving ability, and it paints a very consistent picture. Cannabis is impairing, but only slightly, and it's well within the impairment we tolerate with other substances. It takes extreme amounts of THC to impair someone as much as a .08 BAC, for example.

    That's what the actual research shows. It's favorable to cannabis. And that's why the director of the NHTSA is playing dumb.

  • Re:Easy (Score:5, Insightful)

    by Artraze ( 600366 ) on Wednesday November 21, 2012 @11:22AM (#42055403)

    > Now if any state had the testicular fortitude to challenge them over their utterly unconstitutional use of the threat
    > of withholding federal highway funds from states that failed to raise the drinking age to 21,

    As another poster pointed out: it already happened and they lost.

    The problem is simple: The federal government has the power to levy an income tax all citizens without any real accountability. Thus, they can just 'steal' tax money from a state by raising taxes and keeping the increased revenue (unless you behave). Sure, the state _could_ levy its own transportation taxes and eschew the federal money, but now its people are getting double taxed and not seeing the benefits of half of it. As a result people leave, protest, etc. The only real ability to allow states the ability to control the drinking age it to change the federal law, unfortunately. (Or maybe an amendment prohibiting redistribution of money to the states?)

    Anyways, another challenge would almost certainly go down in flames: SCOTUS already hinted (IIRC) that they're okay with the 'Obamacare' no-health-insurance penalty if it's constructed as a tax, so they're probably okay with the general idea of the federal government coercing behavior with taxation. I'm looking forward to our free speech tax.

  • Re:Easy (Score:5, Insightful)

    by Runaway1956 ( 1322357 ) on Wednesday November 21, 2012 @11:51AM (#42055775) Homepage Journal

    Pot is still ILLEGAL everywhere that the United States federal government has jurisdiction. Don't make a stupid mistake, and get busted because you THINK that pot is legal.

    What the new state laws amount to, is the states have told the feds, "We're not going to enforce your stupid laws for you, and we're turning a blind eye unless someone is really being stupid."

  • Re:Nonsense (Score:4, Insightful)

    by ColdWetDog ( 752185 ) on Wednesday November 21, 2012 @12:07PM (#42056007) Homepage

    Actually it should be pretty easy. Video cameras in police cars are pretty much ubiquitous. If you're wandering, going too fast / too slow or whatever and the policeman (or a citizen with the same tech) gets a video of the car with you getting out of it - you're driving impaired. It doesn't really make a difference if it's due to marijuana or benadryl - you shouldn't be driving.

  • Re:Easy (Score:5, Insightful)

    by C0R1D4N ( 970153 ) on Wednesday November 21, 2012 @12:14PM (#42056137)
    And this is why we should be signing secession petitions. Not because one of the twin candidates lost, but because the Federal government long ago began overreaching.
  • by Enigma2175 ( 179646 ) on Wednesday November 21, 2012 @12:36PM (#42056483) Homepage Journal

    marijuana use in the absence of other substances impairs driving very little

    Yeah, my stoner roommate used to say shit like that too. Of course, he also claimed it helped him study, but unless one considers watching the Cartoon Network all day "studying" then I never saw any evidence of it. And, while I never was a full-time stoner myself, I did smoke enough to know that I sure as shit wouldn't have felt comfortable driving on it (or doing anything else that required concentration).

    Of course, I'm sure the stoner brigade can produce a plethora of studies claiming that weed is a fucking miracle cure-all with no downsides whatsoever, written by the same kind of biased researchers that produce studies showing that burning shit-tons of coal is great for the environment.

    So your "gut feeling" is more relevant than peer-reviewed studies because you "feel" that the researchers are biased? Please refute the data with data, not emotional reactions to the "stoner brigade". For example, here is a study on driving under the influence of Cannabis that cites several other studies, if you have a problem with the data please point out the problem instead of resorting to logical fallacies.

    http://epirev.oxfordjournals.org/content/21/2/222.full.pdf [oxfordjournals.org]

  • Re:Easy (Score:4, Insightful)

    by BitZtream ( 692029 ) on Wednesday November 21, 2012 @12:45PM (#42056613)

    You know nothing about stoners.

    They don't sit there for a long time because their sense of time is distorted. They sit there because they aren't paying attention to the light itself and are paying attention to other things in the environment around them.

    In reality, the red light turning green is almost but not quiet the LEAST important thing about driving. If you argued running red lights you might have something, except that doesn't happen either.

    Doctors stoned on pot don't scare me even a little bit, you'll know from his/her actions if they are incapable of doing their job. I'm far more afraid of someone being fucked up on an opiate like Vicodine than pot. If you knew anything about the two you would be too. The opiate may not show its symptoms and still cause serious mental effects. Pot on the other hand makes it obvious, and when it doesn't ... it doesn't, and its not that big of a deal.

    You don't need a drug test to tell if a pothead is incompetent. If you pull him over because of his bad driving, thats enough. Same applies to alcohol for that matter. The tests are just there to cover cops asses. The requirements for a test are there to prevent cops from abusing the illegal nature of it. In both cases, determining if someone shouldn't be doing something because they are impaired is done WITHOUT a test. The test is just to prevent bad people (overzealous cops and lawyers representing guilty) from abusing otherwise perfectly legitimate methods of accomplishing a task.

    I agree that impairment is not acceptable in many situations, but you have absolutely no idea what causes that impairment, you're just parroting someone elses statements.

In seeking the unattainable, simplicity only gets in the way. -- Epigrams in Programming, ACM SIGPLAN Sept. 1982