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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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  • Easy (Score:5, Funny)

    by Anonymous Coward on Wednesday November 21, 2012 @09:17AM (#42054017)

    Just ask the driver what snack they'd like from the police car.

    • 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 :

    • by phorm ( 591458 ) on Wednesday November 21, 2012 @12:48PM (#42056665) Journal

      Impaired drivers are easy enough to spot.
      A drunk driver will run a stop sign
      The stoned driver waits for it to turn green.

  • 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.

    • Re: (Score:3, Informative)

      by ozmanjusri ( 601766 )

      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

      • "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.

        Or so says the sales literature.

        • Re: (Score:3, Informative)

          by Anonymous Coward

          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

      • 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_bob@[ ] ['hot' in gap]> 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 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.

            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.

        • by rgbatduke ( 1231380 ) <> on Wednesday November 21, 2012 @11:13AM (#42055299) Homepage

          Bear in mind also that the normal risk of fatal crashes is low, so doubling it is doubling a number very near zero as it is.

          Contrast that with alcohol (quote from a 1991 NIH article):

          "Based on driver fatalities in single-vehicle crashes, it was estimated that each 0.02 percentage increase in the BAC of a driver with non-zero BAC nearly doubles the risk of being in a fatal crash."

          That is probably not quite a beer's worth of alcohol for most body weights. So to put it another way, somebody who smokes pot while driving -- not "before", but during (a thing that in my youth I did with remarkable frequency) -- is roughly as impaired as if they had had just consumed a single beer. At those levels one does have to wonder about the error bars in the study -- statistically resolving one near-zero from another near-zero is actually remarkably difficult and requires ever so many samples and a totally unbiased sampling scheme with a complete lack of confounding variables -- so your assertion that the actual risk might even go down in those that aren't smoking pot and drinking a beer (where the latter is also difficult to detect and also doubles your risk all by itself) is not without possible merit.

          Again from the article here: []:

          "At BACs in the 0.05-0.09 percent range, the likelihood of a crash was at least nine times greater than at zero BAC for all age groups. Younger drivers with BACs in the 0.05-0.09 range had higher relative risks than older drivers, and females had higher relative risks than males. At very high BACs (at or above 0.15 percent), the risk of crashing was 300 to 600 times the risk at zero or near-zero BACs."

          Note that at BAC's that are still in the legal range in most states, single car fatalities are nearly an order of magnitude greater than the single "doubling" of risk for immediate use of marijuana. That strongly suggests that the best thing to do about "impairment" from marijuana is -- ignore it, or as suggested above, use a field sobriety test, not a blood or saliva test. It is more or less irrelevant to driving skill. I would say (again, based on extensive experience) that this is not entirely true -- one can eat or smoke enough, potent enough, marijuana that driving is ill-advised, but in those cases field sobriety tests would be nearly impossible to pass as well. But it is actually somewhat difficult to get that stoned, and most pot smokers that I knew didn't want to drive when they were -- too scary.

          But the simplest proofs are this. Whether or not it is legal, smoking pot and driving has been nearly universal forever among those that smoke pot. Most states are utterly unable to test for it, yet estimates of prevalence of usage (almost certainly low) suggest that anywhere up to 1/3 or 1/2 of people in certain age ranges at least occasionally smoke. Yet there is no positive association with this same group being a high risk on the road, outside of its tendency to drink. Alcohol is indeed a dangerous substance when it comes to driving, for obvious reasons, even for relatively small amounts. Pot is not, not until consumption is at extreme levels.

          The last thing that confounds this is age. The distribution of fatal and non-fatal accidents with age is quite scary. A stoned 40 year old -- I mean a seriously wasted 40 year old stoner -- with a risk of accident 3 times his age-linked norm -- is a safer driver than a stone cold sober 19 year old. "Silverbacks" -- drivers on the high side of 75, where one's eyesight, hearing, and brain are all breaking down -- are safer still. Why? Because they drive (sober or not) carefully, and in particular far more conservatively than younger risk taking overconfident drivers. I'm living through my own sons' driving experience -- one at age 17 has his first car, now multiply scarred from driving it a whole month. One now 22, who at 18 took his eyes off of the road

      • 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).

    • I have friends who train some pretty advanced Parkour and freerunning while high.. and in fact I still have decent balance these days even when I'm drunk (I can still balance fine along a half-inch wide railing after having say the equivalent of 5 beers), likewise from all the Parkour training.. so testing people's balance and such isn't a very precise measure IMO.

      It's really interesting that pot is being legalised. It actually makes me think that the US political system is working as it should in some rega

      • Re: (Score:3, Insightful)

        by MakerDusk ( 2712435 )
        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 Anonymous Coward on Wednesday November 21, 2012 @09:20AM (#42054043)

    I know this is going to be a really odd way to detect impared drivers as far as people think but it is quite imperical and correct. You simply have the person do a coordination test with a video game type device. Impared drivers will show up whatever the reason. This can also be determined by blink rate and by detection of eye movements. It can be done very rapidly and has been in use by some municipal bus systems for some time with quite spectacular reductions in accidents. In fact this could be built into cars and we could have the car simply park if the driver is impared. (WOW! No arrest needed!) How about this wild idea. Skipping the police and stopping filling our jails and stopping all the fines etc while achieving the goal of public safety. It detects all types of imparement and doesn't bother wasting time on any other issue. Sleepy is detected too.

    This is going to get to be a moot point shortly as the cars will have things like advanced adaptive cruise control that essentially drives the car. How about Google's self driving car etc. I think we are going to ban driving of cars by humans very shortly as they simply are the most dangerous part of the car driving system. You know the NUT behind the wheel is the most dangerous part of the car.

    • How can you tell if the person is under the influence of something or if they are merely a statistical exception to the norms?
      • 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.

        • if you use that as your measurement stick, probably 90% of 'moms with kids' would fail the 'are you distraction free enough to drive?' test.

          we all know this is true, too. soccer moms scare me WAY more than drunks or any other intoxicated driver does. the thing is, drunks know they are drunk (usually) and so they at least try to be careful. moms, otoh, think things are perfectly fine even though little johnny is screaming his head off in the back seat and slapping his sister suzie. each time the mom turn

        • 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: (Score:2, Insightful)

        by Anonymous Coward

        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.

    • Ah, silly beanie, video game tests won't work, not for somebody who has "practiced" playing video games high (which would very likely be everybody under the age of 30 and a lot of people older than that).

      Back in the days when I used to get high daily I also used to play pinball and ping pong and other games involving nearly instantaneous reflexes in order to succeed. I was truly excellent at both, high. I played the best evening of ping pong in my life high one night, with a friend who was also high. We

  • Well... (Score:4, Interesting)

    by Anonymous Coward on Wednesday November 21, 2012 @09:21AM (#42054047)

    Here is my personal anecdote.

    I've been driving high nearly every day for almost 20 years, commuting at least 100 miles a day for 17 of those. I have never been in an accident & my last ticket (41 in a 30) was over 8 years ago.

    I don't drink & drive at all, that shit is dangerous.

    • Re:Well... (Score:4, Interesting)

      by xclr8r ( 658786 ) on Wednesday November 21, 2012 @09:38AM (#42054193)
      I'm sure as you well know.. different people are affected in different manners by THC consumption. Some get overly paranoid, some overly talkative, some think everything is ground breaking new idea, and some do become worse drivers. I've witnessed someone become impaired while smoking when s/he thought that there was no affect on his/her driving. There definitely was an impairment particularly merging on highways with those massive looping turn-arounds. I made the individual stop and took over after a heated argument.

      Am I saying your impaired? No... but there are some people who can't handle themselves and aren't aware that they are not in full control of their faculties.

      I just really hope fork lift drivers in the big box hardware stores are careful and don't use right before their shift. However, I expect to see accidents here. I'm glad this has been legalized in those states but hopefully this is enjoyed responsibly.
      • I'm sure as you well know.. different people are affected in different manners by THC consumption.

        This is something more people need to pay attention to. I myself for example after only one or two puffs will feel seasick, dry mouth, confused, and ready to vomit (if I have one or two more, I will vomit). After that, I pretty much want to curl up, sleep and get rid of the nastiness going on in my brain. Obviously, I gave up trying it after four or five times of the same effects (friends tried to tell me that it's like that for everyone the first time, but gets more fun on subsequent uses - for me, it d

      • 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.

  • by TheRaven64 ( 641858 ) on Wednesday November 21, 2012 @09:22AM (#42054053) Journal
    The blood alcohol level is a red herring. It correlates with impairment, but a number of other factors also affect it. The test should be for reactions and situational awareness. If you fail for any reason, then you should be prevented from driving. If you fail and also have been taking drugs that are known to cause this kind of impairment, then you might get some extra penalty.
    • by Hentes ( 2461350 )

      This. If you can't test for the drug, test for reactions. That's cheap, easy and relatively portable. If a person fails the test, then take a blood sample.

    • by sunderland56 ( 621843 ) on Wednesday November 21, 2012 @09:33AM (#42054131)

      This. Right now if someone hits and kills a pedestrian, it's called an "accident" and they go free if they're sober - but they go to jail for many years if they had a drink. It doesn't matter that incompetent driving caused the death - the only time a driver is punished appropriately is when they had a drink.

      A test for competency would also get a lot of older drivers who cannot drive safely any more off the road.

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

    According to NORML [], 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:;2-R/abstract [] ) 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.

      • the prison-industrial complex being profitable

        That is only really an issue in the US with for-profit prison systems. In most of the rest of the world, sending someone to prison is a last, expensive resort.

      • While I agree that combining pot and alcohol is much more impairing than just using one or the other, when you combine almost any drug with alcohol the effect tends to be extreme impairment. A couple beers and a couple Vicoden is a lot worse than several beers, for example.

        Regardless, this only highlights how BAC is a poor determinant for impairment. Like you mention, fatigue tends to be worse than drunkenness. I think if a person can't pass a field sobriety test because of fatigue they should be given the

    • So, instead of developing a suite of testing tools for each new and exciting drug that hits the market (black or pharmacy) why not come up with a system that tests actual impairment? I would think a simple device that tests reaction time, decision making, and coordination would be enough to consistently identify people driving impaired by anything. Then give the same tests at the DMV with more stringent requirements each time a person renews (most places every 5 years). And yes, that would catch people i

    • I once saw a documentary where some people did a driving test while baked, they drove exactly like every single person does in my area. Slow, hesitant, uber-cautious.

  • by aclarke ( 307017 ) <spam.clarke@ca> on Wednesday November 21, 2012 @09:31AM (#42054117) Homepage
    I was pretty shocked at how high the (uncited) statistics were in the summary, of 16.3% having used alcohol or drugs, with "half them [sic] high on marijuana". I decided to do a very small amount of poking around myself, and came across []. It makes these two comments:

    The first-ever “National Roadside Survey of Alcohol and Drug Use by Drivers”, conducted by NHTSA, found that 16.3 percent of nighttime drivers were drug-positive, with marijuana (THC) at (8.6 percent) being the most commonly detected drug.


    In fall 2010, six cities in California (Anaheim, Bakersfield, Eureka, Fresno, San Rafael, and Torrance) conducted nighttime weekend “voluntary” roadside surveys primarily to gather data on marijuana use among nighttime drivers. The results were that 8.4 percent of the drivers providing oral fluid were positive for marijuana and 7.6 percent of the breath tested drivers tested positive for some amount of alcohol.

    These are two different surveys, but the second one shows a slightly different picture than "half them high on marijuana". 8.4% in this study showed some presence of marijuana in their saliva. From the summary, I gather that all that really means is that 8.4% had smoked pot some time in the last couple weeks. 7.6% had had some amount of alcohol still detectable in their breath, although that includes people with a trace amount, well under the legal limit. So, I'm not going to adjust my general expectations of other drivers to think that one in every 6 drivers at night is drunk and/or high.

  • In some places (parts of Australia for example) the law simply says you aren't allowed to drive and have any trace of THC in your hair/saliva/blood. This works because the drug is already outlawed. However, it's not fair to say that the drug is legal, but you aren't allowed to use it within a week (or whatever) of driving.

    However, as with alcohol, the problem isn't the numbers, it's the impairment. With alcohol now, the law doesn't even care about impairment. If your blood alcohol level (as measured by a ma

  • The summary (and I am going to bet the article as well) makes a faulty assumption. It assumes that there is a way to measure some substance related to marijuana that correlates to level of impairment in the same way that blood alcohol level correlates to impairment with regards to alcohol consumption. There is at this time no evidence that such a substance exists.. Of course as an anonymous coward points out elsewhere in this thread there is a second faulty assumption in this article. That assumption is tha
  • Driving within three hours of smoking pot is associated with a near doubling of the risk of fatal crashes.

    Oh dear, that's almost as dangerous as dialing a phone [].

    Given how the police have broad surveillance powers to correlate cell phone logs against the mandatory GPS units installed in our cars in order to determine if we were dialing while driving, it is not unreasonable that we demand they have similar powers over knowing when pot smokers inhale their illicitly legal drug.

    • Given how the police have broad surveillance powers to correlate cell phone logs against the mandatory GPS units installed in our cars in order to determine if we were dialing while driving, it is not unreasonable that we demand they have similar powers over knowing when pot smokers inhale their illicitly legal drug.

      Yes it is. Instead, we should demand that they do not have those broad surveillance powers. Don't be a henchman.

  • Instead of worrying about tolerances and equivalent BAC levels, just come up with a field sobriety test that can detect if someone is too impaired to drive. The problem with a pot BAC is that people react differently to THC. One person might throw up and become stoned from a few good hits while another may feel little to noting at all from the same dose.

    I have a friend who has two jobs, goes to school for his bachelors degree, has a wife and a new-born son. When I asked him how he copes he replied: "Copious

    • I have a friend who has two jobs, goes to school for his bachelors degree, has a wife and a new-born son. When I asked him how he copes he replied: "Copious amount of marijuana, bro." He smokes when he wakes up, smokes on his drive in to work, smokes during lunch, smokes on his way to night classes or his second job and a few hits at night before bed.

      Similarly, I have known several people who were functioning alcoholics. What exactly does this prove?

  • 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.'"

    Sorry guys, but we don't know what level of alcohol actually makes people too impaired to safely drive, either. Yes, we have a hell of a lot better idea than with THC, but put bluntly, some people can function better at .015 than others can
  • by Rooked_One ( 591287 ) on Wednesday November 21, 2012 @09:48AM (#42054287) Journal
    So number 1... which is all I really need, is how did they determine half the people pulled over were smoking cannabis? They say in the article they can't.

    2 - the numbers are probably skewed in the way of cannabis because the US cannot lose any wars. And the war on drugs, is a war. So this is just a continuation of the scare tactics we've seen all too much.

    3 - I know pharmacists. They say at least 50% of the population is on lortabs, percocets, etc... Stuff with hydrocodon and oxycodone. It could be easy to say, that chances are if you're reading this, you have a prescription.

    Bottom line, the study is flawed and just a continuation of scare tactics IMVHO.
  • 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 macs4all ( 973270 ) on Wednesday November 21, 2012 @10:11AM (#42054545)
    Compare the following statements:

    Driving within three hours of smoking pot is associated with a near doubling of the risk of fatal crashes.


    'We don't know what level of marijuana impairs a driver.'"

    One of those two statements HAS to be a lie.

    Personally, I have NEVER heard of a story where Marijuana "impairment" alone has been implicated as the causal factor in any traffic fatality.

    And that "one week" figure is also completely bogus. Even a drugstore urine test can detect Marijuana use for around 30 days.

    There have been no reputable studies that show that driving while high on pot is significantly more dangerous than driving while "sober". Any study of accidents where Marijuana use was also detected would be hard-pressed to find that the pot "impairment" was the cause. But watch the fake statistics start to pile in, by "scientists" looking for their next "Grant-Welfare" money, as the NIH helps the Federal Government "make the case against pot".

    Mark my words.

    • by RazorSharp ( 1418697 ) on Wednesday November 21, 2012 @10:40AM (#42054859)

      I think the problem is that every time someone's been in a crash and pot was found on them or they tested positive for pot at the hospital, the authorities "associated" pot with the crash. This is a classic mix up of correlation and causation. They don't realize that pot is found on a lot of people who are involved in crashes because it's so ubiquitous, not because it actually causes people to wreck.

  • by Charliemopps ( 1157495 ) on Wednesday November 21, 2012 @10:25AM (#42054695)
    They already have a test... its the Field sobriety test, and it's a hell of a lot more accurate than a blood test. If you gave my mom 1 beer, and put her on the road, I'd be terrified. If you gave my uncle a 6 pack, he could likely drive just fine. But he'd fail the blood test while my mother would not. The field sobriety test on the other hand would show who really shouldn't be driving. Irrelevant of the drugs you're taking, your reaction time, focus, and balance are the only true way to measure if you should be driving or not. Because that's what matters right? If you can DRIVE? Or are we trying to do something else here?
  • by Type44Q ( 1233630 ) on Wednesday November 21, 2012 @11:49AM (#42055745)

    Colorado State Police have announced that they plan to start aggressively enforcing minimum speed limits...

Don't get suckered in by the comments -- they can be terribly misleading. Debug only code. -- Dave Storer