With Pot Legal, Scientists Study Detection of Impaired Drivers

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.'"

Comments

Easy

[Anonymous Coward]

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

Re:Easy

[aicrules]

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.

Re:Easy

[macs4all]

They didn't Decriminalize it; they LEGALIZED it.

There's a difference.

Re:Easy

[rgbatduke]

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).

rgb

Re:Easy

[Anonymous Coward]

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.

Re:Easy

[Grond]

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. 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

[CohibaVancouver]

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.

Re:Easy

[Artraze]

> 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

[Anonymous Coward]

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

Re:Easy

[Runaway1956]

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:Easy

[C0R1D4N]

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.

Re:Easy

[rot26]

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

[BitZtream]

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.

Re:Easy

[UltraZelda64]

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.

Actual Detection of Impared Drivers

[Anonymous Coward]

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.

Re:Actual Detection of Impared Drivers

[Cenan]

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.

Re:Actual Detection of Impared Drivers

[Endo13]

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

Well...

[Anonymous Coward]

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...

[Hatta]

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.

Good. Start testing the correct thing.

[TheRaven64]

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.

Why not factor in actual research?

[dkleinsc]

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.

Re:Why not factor in actual research?

[Stirling Newberry]

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 ) 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:Good. Start testing the correct thing.

[sunderland56]

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.

Re:Field Sobriety Test

[Internetuser1248]

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.

Re:Nonsense

[KClaisse]

The hyperbole is strong with this one....

Re:Field Sobriety Test

[rgbatduke]

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: http://www.ncbi.nlm.nih.gov/pubmed/1875701:

"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

Re:Field Sobriety Test

[Enigma2175]

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

Re:Field Sobriety Test

[MDMurphy]

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

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.

Stoned VS drunk

[phorm]

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