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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 dkleinsc ( 563838 ) on Wednesday November 21, 2012 @09:25AM (#42054071) Homepage

    According to NORML [norml.org], what basically happens when someone is driving while on marijuana is that while they're somewhat impaired, they also drive more cautiously and leave more space around them. The net effect is that while they're annoying, they aren't all that dangerous.

    By contrast, when someone is driving drunk, they tend to be both impaired and reckless. The net effect is that thousands of people each year are killed by drunk drivers.

  • by Stirling Newberry ( 848268 ) on Wednesday November 21, 2012 @09:35AM (#42054157) Homepage Journal
    This is a bad summary. Research, not just in the US, has been on going for over 40 years. When put to empirical test (For example: http://onlinelibrary.wiley.com/doi/10.1002/(SICI)1099-1077(1998110)13:2+%3CS70::AID-HUP50%3E3.0.CO;2-R/abstract [wiley.com] ) Marijuana, by itself, is low to moderately impairing, especially in doses sufficient to produce a high. However, when combined with even small amounts of alcohol, even half legal BAC limits, the effect was much larger. Add this to an aging population and there is an area of concern, particularly because other aspects of decriminalization, legalization, or medicalization are compelling.

    For comparison texting is much worse, and distraction and fatigue produce similar results. We could have the computer on a car detect impairment based on driver response however. But that too raises questions.

    It is the mechanization problem that has been one of the economic factors behind drug criminalization for the better part of a century, besides, of course, the prison-industrial complex being profitable and being a good place to warehouse psychopaths and feed into common racism and fear of crime.

  • Re:Easy (Score:5, Informative)

    by aicrules ( 819392 ) on Wednesday November 21, 2012 @09:42AM (#42054217)
    Not entire US. Washington state and Colorado. The vote was part of the natoinal election 11/6/2012. It will take a while for it to meaningfully take effect, and with Federal government still classifying it as an illegal drug, we may get to see a nice states' rights case soon eough. I look forward to that as I always like to see the Federal government put in its place.
  • by ozmanjusri ( 601766 ) <aussie_bobNO@SPAMhotmail.com> on Wednesday November 21, 2012 @09:50AM (#42054305) Journal

    Or just pay attention to what's happening in the rest of the world:

    "Rather than blowing into a breathalyser, drivers will be asked to provide a saliva sample by placing a small absorbent pad on their tongue for a few seconds. The Securetec Drugwipe II Twin device is supposed to take about five minutes." (In Victoria, another test is mentioned in the enabling legislation, called Cozart RapiScan.)

    "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]

  • Re:Well... (Score:5, Informative)

    by Hatta ( 162192 ) on Wednesday November 21, 2012 @09:55AM (#42054355) Journal

    I just really hope fork lift drivers in the big box hardware stores are careful and don't use right before their shift.

    I guarantee you, every warehouse worker that wants to be stoned on the job is already stoned on the job.

  • Re:Easy (Score:5, Informative)

    by macs4all ( 973270 ) on Wednesday November 21, 2012 @09:56AM (#42054363)
    They didn't Decriminalize it; they LEGALIZED it.

    There's a difference.
  • by Internetuser1248 ( 1787630 ) on Wednesday November 21, 2012 @10:00AM (#42054411)
    Even the summary covered that: "However, THC can remain in blood and saliva for highly variable times after the last use of the drug."

    While on the subject, does anyone have the source for this quote? "Driving within three hours of smoking pot is associated with a near doubling of the risk of fatal crashes" I find it doubtful and would like to read the methodology. In my experience impairment from marijuana use in the absence of other substances impairs driving very little. There are some issues with concentration and alertness but in most people it also has the effect of lowering their speed and therefore I find it hard to believe the crashes are fatal so often. Unless they pull out in front of a speeding driver or something. Of course this is all speculation based on personal experience, hence why I want to read the study referred to in the summary. It isn't mentioned in tfa either in those words.
  • by ozmanjusri ( 601766 ) <aussie_bobNO@SPAMhotmail.com> on Wednesday November 21, 2012 @10:11AM (#42054529) Journal

    Role of Cannabis in Motor Vehicle Crashes, Michael N. Bates and Tony A. Blakely 1999

  • by Anonymous Coward on Wednesday November 21, 2012 @10:29AM (#42054737)

    That's absolutely not true, saliva testing is almost identical to a urine sample, meaning 2 weeks to a month to get a clean test. Only difference is that saliva testing is more accurate i believe. They already do mouth swabs for probation and stuff, why would they only want to know if the user did it in the past 5 hours? And FYI: THC is in marijuana, so i'm not quite sure how THC ends up on the 24 hour list and marijuana is on the 5 hour list. Misinformation at its best right here folks

  • Re:Easy (Score:4, Informative)

    by Anonymous Coward on Wednesday November 21, 2012 @10:44AM (#42054895)
    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.
  • by betterunixthanunix ( 980855 ) on Wednesday November 21, 2012 @10:45AM (#42054921)

    24 hours for all the other drugs, including amphetamines

    Considering the fact that amphetamine (e.g. Adderall) affects a person's system for about four hours, I fail to see how this is a good thing. I also fail to see how it can be a good thing given the large number of people who use amphetamines legally, as prescribed by a doctor. Therapeutic doses of amphetamines will improve a person's ability to drive, so I have to wonder why we would even be concerned about people driving under the influence of amphetamines.

    24 hours for all the other drugs, ... and THC

    THC is the drug in marijuana, so you must be mistaken (or this is a scam).

  • Re:Easy (Score:5, Informative)

    by Grond ( 15515 ) on Wednesday November 21, 2012 @10:53AM (#42055019) Homepage

    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.

    A state did challenge the federal government over that very thing. It lost [wikipedia.org]. The decision was 7-2, and with the current makeup of the Court it's unlikely that it would hear a similar case.

  • Re:Easy (Score:3, Informative)

    by fustakrakich ( 1673220 ) on Wednesday November 21, 2012 @11:13AM (#42055285) Journal

    But getting the US government out of the marijuana game as the first step...

    Then we have to keep the UN from meddling [boston.com]...

  • Re:Easy (Score:4, Informative)

    by asylumx ( 881307 ) on Wednesday November 21, 2012 @11:18AM (#42055347)
    Several traffic violations are "decriminalized" but they are still civil offenses. Ever face a jury trial for speeding? No. Why? Because it's not a criminal offense, but it IS illegal. That's the difference. Something can be illegal without being a criminal offense.

    In this case, small amounts of marijuana are actually LEGAL (not just non-criminal) -- at least according to state law.
  • Re:Easy (Score:4, Informative)

    by Anonymous Coward on Wednesday November 21, 2012 @11:27AM (#42055453)

    Although not particularly scientific, British TV show Fifth Gear tested stoned driving : http://www.youtube.com/watch?v=IA7_ajF741I

  • Re:Easy (Score:4, Informative)

    by rot26 ( 240034 ) on Wednesday November 21, 2012 @12:17PM (#42056171) Homepage Journal
    The Obama/Holder administration has been fairly aggressive in California in shutting down producers. Those medical pot shops do NOT operate with impunity, they are randomly raided and shut down on a regular basis, in addition to being robbed by the street pharmacists they replaced.
  • Re:Easy (Score:4, Informative)

    by kilodelta ( 843627 ) on Wednesday November 21, 2012 @12:21PM (#42056255) Homepage
    An in other areas of the U.S. they have moved enforcement from criminal to civil. Here in RI you can have up to an ounce, you can't smoke in public, and they actually license growers. It's all very quiet of course but it exists.

    If you are caught in public it's like a $100 fine on the civil side, not criminal.
  • by MDMurphy ( 208495 ) on Wednesday November 21, 2012 @12:36PM (#42056485)

    In the study referenced there are LOTS of "conclusions" mentioned that can be taken out of context of the article. This be because the paper references many other studies and quotes their conclusions or observations. The bulk of the paper points out positive and negative aspects of previous studies. The paper itself does not present the conclusion of "a near doubling of the risk of fatal crashes" as suggested above. There may be another paper with that conclusion, but it's not this one. If that number came from one of the other studies that this paper cites, it would be interesting to see how this paper's authors address that conclusion.
    http://epirev.oxfordjournals.org/content/21/2/222.full.pdf [oxfordjournals.org]

    There are three points at the end of this paper:

    "Overall we conclude that the weight of the evidence indicates that:"

    1. No evidence that consumption of cannabis increases the risk of culpability for fatal traffic crashes and may decrease them.
    2. The evidence for the combined effect of cannabis and alcohol relative to alcohol alone is unclear.
    3 It is not possible to exclude that cannabis use, with or without alcohol leads to an increase risk of road traffic crashes causing less serious injuries and vehicle damage.

  • Re:Easy (Score:4, Informative)

    by UltraZelda64 ( 2309504 ) on Wednesday November 21, 2012 @02:20PM (#42057941)

    In my state, marijuana is "decriminalized." I am waiting for the day that it is "legalized," and I have been waiting for years. I never thought I would see even one state legalize it. Hopefully it won't take too much longer for the rest of the states to catch on.

    Anyway... in my state there are no stores that are legally allowed to sell marijuana, so you can't get it legally in any way, shape or form. You are breaking the law just by buying it, and not paying taxes (double whammy!). You're not even allowed to grow it yourself to make up for this and avoid the drug dealers, and if you get caught with any amount of plant material or any number of plants it will be confiscated (probably for the police to smoke themselves). Get caught with a pipe, bong or any other kind of "drug paraphernalia" and it will also be taken away. You may not be labeled a criminal, but you will still likely be penalized by the state, in addition to them taking all your shit that they can find either on you, on or in your property, or generally on the scene.

    By contrast, Colorado is supposedly going to not only allow the drug to be regulated, taxed and sold in stores like any other legitimate commercial good (to people of a certain age, obviously), but it's even going to allow people to grow up to six cannabis plants and own/possess up to a certain amount of dried plant material/marijuana itself. Chances are, unless you're suspected of drug trafficking or you're doing something really stupid (like driving with a joint in your hand), the police won't take anything away from you, and they might or might not just try to find something else to bust you for instead. That beats the living fuck out of Ohio, in which--honestly--it might as well still just be considered illegal here. I don't know about Washington's exact planned laws, but they're legalizing it too, so no doubt it will be similar.

    No matter what, decriminalized, legalized, whatever--this only covers personal use and possession of small amounts; you can't have, say, several ounces on you or dozens of plants, or you'll immediately be suspected of drug trafficking and be slapped with some pretty hefty fines and other penalties, probably including jail time and labeled a felon if you have enough. The real difference is the complete lack of penalty as long as you stay within the limits of the law where it is legalized, as well as the fact that you don't have to go to drug dealers in the black market and buy it illegally just to obtain it.

Air is water with holes in it.