Question about marijuana testing after an auto accident.

Let’s say there is a guy who drives a bus for a living. This guy, (I’ll call him Don) enjoys unwinding after a long day of bus driving by smoking the evil weed. Don never ever partakes before going to work, only partaking right after work, and finishes at least 12 hours before he starts his shift. Let’s say Don has an accident which causes him to be tested for drugs. Is the test they preform going to differentitate between Don having drugs *in his system * and being *under the * influence, or does it just shows drugs in system, must have been high, etc. Case 2, let’s say Don smokes the evil weed once a month or so. Say he gets high June 7. On June 30 he has a wreck and is tested for pot, and the pot from June 7 is still in his system. Again, will the test administrator distinguish between “old” pot in the system, and pot fresh enough to have possibly played a role in the accident?

About the only thing I’ve ever seen a drug test be able to differentiate was the level of the drug, not whether it was new or old.

If regulations allow something other than zero tolerance, it’s up to the appropriate judge to determine whether the amount of the drug in the system contributed to the accident.

I’ve done some drug testing, and usually the way it works is to set the bar pretty high for the initial screening, because it’s a quick and dirty test done cheaply. The detection limit of these tests might be 50 ug/ml THC metabolites in urine. GC/MS testing might lower the limit to 5 or 10 ug/ml or so. If they really want to get right down to the limit, hair testing and GC/MS might show marijuana use months after the fact.

Each improvement in technique adds to the cost, so they might just use the quick and dirty dipstick for random testing, but if an accident occurred they could get pretty rigorous.

Was Don required to take a drug test in order to qualify for the job of being a bus driver? Was a statement signed at the time of initial employment giving Don’s permission to submit to drug testing? These will sometimes state the employers drug policy and Don’s agreement to abide by them during his term of employment or be dismissed. If so, any level of pot in system after an accident would most likely be grounds for Don’s dismissal, even if they can’t prove it caused the accident. Point is, Don would be guilty of violating his employment agreement not causing an accident per say. Sucks to be Don, is he a close friend of yours?

In my post above, I meant ng/ml, not ug/ml. Sorry for the mistake. If you’ve got ug/ml levels of THC metabolites in your urine you’re having way too much fun.

From what I’ve observed in NTSB reports, it is possible to determine from the level of THC metabolites in urea the last time within a reasonable window plus or minus, that the cannabis was used. Bottom line is that a bus driver needs a CDL, and the FMCSA regulations consider THC to be a prohibited substance and it’s use on or off duty is prohibited. CDL holders may be tested pre-employment; reasonable suspicion; post-accident; random; return-to-duty; and follow-up.

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Welcome to the Dope Don.
Now about your post. If your buddy “Don” has evidence of THC in his system after an accident particulary an injury accident, the shit will truely hit the fan. Doesn’t matter that it has been 12 hrs. people will be calling for your err make that “Don’s” head.
My suggestion to “Don” would be to either stop smoking, or find a job where they would have more of a sense of humor about it. Driving a bus with evidence of THC in your system is an invation for an royal ass kicking.

To address the two questions: I have very little doubt that THC would be present after 12 hours. I’m not sure if it would be detectable after 3 weeks, but it’s a very real possibility.
I think that you’re alluding to two different issues as far as the accident is concerned and it’s probably up to a jury to decide if the pot contributed to the accident, if he chooses to go the “not guilty” route If “Don” drives a bus carrying 16 or more people, then he’s required to have a CDL, class “C” license. The presence of illegal an drug in his system is grounds for revocation of the CDL, no matter how long ago he imbibed.
Rick hit it on the head. Don needs to choose between smoking pot and holding down a job that forbids the use of illegal substances.
It may be possible for “Don” to ask for help w/ the substance abuse problem and save his job, I’d guess that the circumstances of the accident would, in large part, dictate the success of that possibility.
This is not a moral judgement, just a practical one.

Since marijuana use is essentially illegal, and there’s no industry to pay taxes or bribes, there’s no motivation to determine an impaired vs unimpaired state. In our ER, there’s alcohol levels, and everything else is +/-

There is no marijuana test that can attest to the level of intoxication at the time of the test. It is looking for the metabolite of the drug, the byproduct your liver spits out after helping to get you straight again.

If alcohol tests worked like that, you could get falling-down-puking drunk on Saturday, and by Wedensday you’d still test drunk.

Regarding Case 2 (your alibi?). After having smoked once, THC should be detectable for three to five days. Maybe a week.

Yeah, I dunno. I’m wondering, was the urine that you gave after the accident saved? Could a more detailed analysis be conducted after the fact? There might be some specific short-term metabolite you could look for.

AskNott makes an excellent point, in that the metabolites being detected may be such that a normal test may hardly be affected at all by smoking once in the past few hours if you’ve been smoking every day for a week. Only a test for short-term metabolites, or better yet THC itself, may reveal such information.

Also, where do you live? Do the juries there think of weed as some insanity-inducing menace, or do they understand it for what it is? That’ll determine how much they’ll care whether or not you were intoxicated.

It sounds like Don’s been a doper for some time already.

I just looked this up last night because I have a friend who is anticipating a drug test any day now. She was a regular pot smoker, and has cut down considerably over the last month. However, the site I checked said that smoking pot 2-4 times per month will take 11-18 days to clear out of your system. I think a single usage smoker takes 5-8 days to leave your body. Problem is, they don’t say how much pot you need to smoke in order to qualify for a “use.” She smoked a joint of good pot with a friend, so my guess is she’ll test dirty.

Re: the bus driver gig…I’m guessing they have a zero tolerance policy due to the nature of the business. I’d say offhand that the word “fucked” will be introduced to the conversation shortly. Good luck to your friend.

Thanks all for the responses. The accident was truly hypothetical- it hasn’t happened yet. This is just something I have always thought about, being a pothead and all, I have a Kafkaesque fear of being a wreck, whether at work or in my car, and be tested and found to be “under the influence” when not actually under the influence. As a follow-up (**Bill Door ** touched on this earlier), are there “severity rules” following an accident to determine if someone gets tested for drugs? Obviously if you are acting impaired even after a fender bender you will get tested, but how “severe” does an accident have to be for a person who is acting and looking completely normal to be tested?

All it takes is suspicion on the part of the investigating officer.

Strong, friendly suggestion: get off the drugs, period. That way, you don’t need to be worrying about it and you won’t be endangering the lives of your passengers.

That’s just how pot works, unfortunately. The question is whether you’re in a job that will test you in case of a mishap. If I recall correctly, if you’re a transport operator they do test you after any accident. There’s no way to determine whether you’re high at the time of the accident or were high earlier, so they don’t try to do so.

I think this is entirely appropriate… if you’re a dishwasher or envelope-licker, go smoke your brains out, I don’t care. If you’re driving a bus, just stay off the weed. I’ve been a pothead in the past and I know that even though the buzz wears off in a few hours, the stupid lingers for days or more.

Cite for how marijuana last smoked 12 hours prior to driving is a danger?

Our OP’s “freind Don”. He’s a bus driver, where if he has to do the old “pee in a bottle” thing he’ll lose his job, *and worse- * but yet he’s still puffing. Thereby the “stupid” from Pot use must carry over! :stuck_out_tongue:

According to NIDA ,


Your own source also says:

Is there any cite anywhere for a person getting in a car accident due to being un-coordinated or learning impaired 12+ hours after smoking marijuana?