DUI and cannabis - Can a fair test be developed?

The fact that cannabinoids remain in the blood stream for an extended period should cast fear into the hearts of all users who drive. If you get into an accident and are given a blood test it may show "intoxication" though you may not have smoked since last night. This I fear could lead to grave liability - both criminal and civil.

The only fair solution to this problem is a test that shows actual current "intoxication" or impairment - not indicators of residual, non-psychoactive cannabinoids. Is such a test being developed? Can it be developed given current technology? Would a spinal tap solve the problem :ugh:? Anyone have knowledge of this?

This is something I think about.
 
kelper,

morninglight

Well-Known Member
The fact that cannabinoids remain in the blood stream for an extended period should cast fear into the hearts of all users who drive. If you get into an accident and are given a blood test it may show "intoxication" though you may not have smoked since last night. This I fear could lead to grave liability - both criminal and civil.

The only fair solution to this problem is a test that shows actual current "intoxication" or impairment - not indicators of residual, non-psychoactive cannabinoids. Is such a test being developed? Can it be developed given current technology? Would a spinal tap solve the problem :ugh:? Anyone have knowledge of this?

This is something I think about.

Isn't a field test administered first? Not every accident requires a blood test.. ?

Then it goes to breath/blood?
 
morninglight,

Tweak

T\/\/34|<
Blood tests actually detect the illicit drug and not the metabolites. THC is only detectable in the blood for a few hours, with chronic users having slight detection for up to 12-24 hours.

Urinalysis can not detect the presence of any illicit drugs, only the metabolites.

That is why I think urine tests are complete BS, a majority of illicit drugs are gone within 1-3 days, so a crack head can pass a piss test from just taking a day or two off. Not so for cannabis consumers, they have to quit a month or more in advance to pass a pee test.
 
Tweak,
Blood tests actually detect the illicit drug and not the metabolites. THC is only detectable in the blood for a few hours, with chronic users having slight detection for up to 12-24 hours.

Urinalysis can not detect the presence of any illicit drugs, only the metabolites.

That is why I think urine tests are complete BS, a majority of illicit drugs are gone within 1-3 days, so a crack head can pass a piss test from just taking a day or two off. Not so for cannabis consumers, they have to quit a month or more in advance to pass a pee test.
Do you know if the 12-24 hours can result in high enough of a detection to make it appear you are under the influence? That would fall in the "last night" scenario and is what concerns me. I don't have the answers to these questions myself - not trying to just be rhetorical.
 
kelper,

OO

Technical Skeptical
This is a topic that needs serious discussion.

In my mind, the only way to determine impairment is by taking a video of how the person is driving.

If they are driving in a manner consistent with being impaired, I don't see why they should be allowed to drive, forget if drugs are involved or not.
 
OO,
the only sort of test which could be administered which would test for current intoxication is a saliva test, since it can only detect THC within 3 hours (i think) of consumption.
 
smoke blunts,

OO

Technical Skeptical
the only sort of test which could be administered which would test for current intoxication is a saliva test, since it can only detect THC within 3 hours (i think) of consumption.
This assumes that there is some kind of relevancy between concentrations of THC in the bloodstream, and impairment, which is actually not what the data suggests. http://www.erowid.org/plants/cannabis/cannabis_driving4.shtml
Marijuana's effects on driving performance were compared to those of many other drugs. It was concluded that THC's effects after doses up to 300 mcg / kg never exceed alcohol's at BAC's of 0.08 g %; and were in no way unusual compared to many medicinal drugs'. Yet THC's effects differ qualitatively from many other drugs, especially alcohol. Evidence from the present and previous studies stronly suggests that alcohol encourages risky driving whereas THC encourages greater caution, at least in experiments. Another way THC seems to differ qualitatively from many other drugs is that the former's users seem better able to compensate for its adverse effects while driving under the influence.
 
OO,
so it really seems the issue here is that the government has a skewed view about intoxicated driving when it comes to THC, which I doubt will be altered anytime in the near future.
 
smoke blunts,

OO

Technical Skeptical
so it really seems the issue here is that the public has a skewed view about intoxicated driving when it comes to THC, which I doubt will be altered anytime in the near future.

*fixed.

More to the point, the public is grossly misinformed when it comes to the techniques used to 'prove' impairment with alcohol.

0.08 Isn't some magical barrier that has only not drunk people below it and only drunk people above it.

Concentrations of compounds in the bloodstream tell you relatively little about impairment, a more objective type of evidence is the kind I suggested earlier.
 
OO,
*fixed.

More to the point, the public is grossly misinformed when it comes to the techniques used to 'prove' impairment with alcohol.

0.08 Isn't some magical barrier that has only not drunk people below it and only drunk people above it.

Concentrations of compounds in the bloodstream tell you relatively little about impairment, a more objective type of evidence is the kind I suggested earlier.
Field sobriety would be more fair, but you know they'll want lab tests if there's a serious accident. Plus field sobriety may be out of the question if you're impaired by the accident itself.

Saliva test is interesting - will have to research. Haven't heard of that being used for DUI. At least that might narrow the window to something more fair.
 
kelper,

t-dub

Vapor Sloth
Kelper, this paper speaks about DUI, cannabis pharmacokinetics, and testing procedures in great detail:

Summy: http://www.idmu.co.uk/drugtestcan.htm
Full PDF: http://www.idmu.co.uk/images/stories/drugtest.pdf

Conclusion: drug testing

Tests for the presence of drugs in bodily fluids of drivers or accident victims may not provide scientifically or legally acceptable evidence that the person was unfit to drive or their actual driving ability was impaired by that drug.

Tests showing inactive metabolites of cannabis do not indicate a current level of intoxication or actual or potential impaired skills. No single test should be relied on as the sole basis for a prosecution.

To determine current intoxication, blood or saliva samples should be tested for unmetabolised THC, and/or the active metabolite 11-hydroxy-THC, with two or more samples taken at recorded intervals of 15 minutes or more to enable back-calculation of the likely levels at the relevant time.

There are major logistical problems with obtaining blood samples without delays which allow active THC levels to fall significantly. An increase in police powers is required to allow saliva samples to be taken at the roadside and then contemporaneously with a later blood sample, to enable back-calculation of blood THC levels to the time of any incident or accident.
 
t-dub,
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OO

Technical Skeptical
Field sobriety would be more fair, but you know they'll want lab tests if there's a serious accident. Plus field sobriety may be out of the question if you're impaired by the accident itself.

Saliva test is interesting - will have to research. Haven't heard of that being used for DUI. At least that might narrow the window to something more fair.
Unfortunately there is no established (or suggested in data for that matter) link between bodily fluid concentrations of a cannabinoid and impairment.

That means that any of these tests would be irrelevant at best.
 
Unfortunately there is no established (or suggested in data for that matter) link between bodily fluid concentrations of a cannabinoid and impairment.

That means that any of these tests would be irrelevant at best.
But will that stop the D.A.!
 
kelper,

OO

Technical Skeptical
But will that stop the D.A.!
It will not, only an educated populous can do that, so do your part and educate.

Changing public opinion is the best way, as D.A.s are members of the public as well, and most do have a conscience, they are just mislead by a skewed public understanding of chemistry.
 
OO,

skippy

Well-Known Member
Blood tests actually detect the illicit drug and not the metabolites. THC is only detectable in the blood for a few hours, with chronic users having slight detection for up to 12-24 hours.

Urinalysis can not detect the presence of any illicit drugs, only the metabolites.

That is why I think urine tests are complete BS, a majority of illicit drugs are gone within 1-3 days, so a crack head can pass a piss test from just taking a day or two off. Not so for cannabis consumers, they have to quit a month or more in advance to pass a pee test.
What would be classified as a chronic user? I didn't realise THC was only detected in the blood for a few hours.
 
skippy,

t-dub

Vapor Sloth
What a TOTAL RED HERRING, I can't believe you posted that in response. If you read it he pleaded guilty to reckless driving because he:
Cogley, a professional driver, reportedly ran multiple red lights and nearly collided with another motorist.
So there is NO law against listening to drum & bass music while driving. Its putting OTHERS at risk while driving like an idiot that is against the law, here as well. Its called VBR (violation of the basic rule) when they can't cite you for something specifically.
 
t-dub,
What a TOTAL RED HERRING, I can't believe you posted that in response. If you read it he pleaded guilty to reckless driving because he:

So there is NO law against listening to drum & bass music while driving. Its putting OTHERS at risk while driving like an idiot that is against the law, here as well. Its called VBR (violation of the basic rule) when they can't cite you for something specifically.
It was a joke.
 

lost nebula

Always Vaping
the only sort of test which could be administered which would test for current intoxication is a saliva test, since it can only detect THC within 3 hours (i think) of consumption.

I am very suspect of the 3 hour estimate. Where I live saliva tests are used commonly for on road dui scenarios and I and a few of my friends have found out they are accurate to at least 72 hours.

On the other hand, because it tests for metabolites I have seen someone smoke a joint and immediately get pulled over for a saliva test and it tested negative, so those saliva tests are dodgy at best.
 
lost nebula,
i think saw that 3 hour figure one time when i was searching through laws and such on the NORML site, but im not sure if i read it wrong or something, but theres a lot of info on that website about different tests and laws and such, so its definitely a good thing to look at if you want to read more about this stuff.
 
smoke blunts,

skippy

Well-Known Member
I am very suspect of the 3 hour estimate. Where I live saliva tests are used commonly for on road dui scenarios and I and a few of my friends have found out they are accurate to at least 72 hours.

On the other hand, because it tests for metabolites I have seen someone smoke a joint and immediately get pulled over for a saliva test and it tested negative, so those saliva tests are dodgy at best.
That's interesting. I live near Nimbin and the hemp embassy did a study of a dozen locals that all used quite significant amounts of weed. Some of them tested negative after two, three and five hours while others tested positive after two and three hours but none tested positive after five hours. So their conclusion was it was ok to drive after five hours.
 
That's interesting. I live near Nimbin and the hemp embassy did a study of a dozen locals that all used quite significant amounts of weed. Some of them tested negative after two, three and five hours while others tested positive after two and three hours but none tested positive after five hours. So their conclusion was it was ok to drive after five hours.
I think I'm going to start wearing a bracelet that says "administer saliva test". I wouldn't want to get stuck with only a blood test.
 
kelper,
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