Marijuana legalization, testing approaches contributes to truck driver shortage: ATRI

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A new report by the American Transportation Research Institute (ATRI) is raising concerns that current approaches to drug testing and the spreading legalization of marijuana in the U.S. are contributing to the shortage of truck drivers. 

Twenty-three states now legalize recreational marijuana, up from 10 in 2019. That means 41.4% of American truck drivers now live in the legalized jurisdictions, up 18.5% during the same period, ATRI notes in its Impacts of Marijuana Legislation on the Trucking Industry report.  

But federal regulations do not allow CDL holders to use marijuana, identifying it as a Schedule 1 drug. 

traffic light with marijuana leaf
(Photo: iStock)

Over half (57.2%) of all positive drug tests in the trucking industry are for marijuana, ATRI says, citing Federal Motor Carrier Safety Administration (FMCSA) Drug and Alcohol Clearinghouse (DACH) data. More than 100,000 drivers were suspended because of failed tests between 2020 and 2022 – a frightening dynamic amid the national truck driver shortage. 

CDL holders who work in the U.S. are subjected to random, pre-employment and post-accidental testing, as well as reasonable suspicion and return-to-duty drug testing, usually performed through a urine test. 

Positive tests vs. impairment 

Unlike alcohol testing, where the traces of alcohol are not noticeable for days or even hours after consumption, marijuana can still be detected for up to 30 days after consumption, increasing the likelihood of positive tests. 

However, a positive test does not indicate the trucker was driving impaired, unless the test was conducted hours after an accident. (One of the studies that ATRI analyzed in its report suggested that drivers should wait five hours after inhaling marijuana before operating any vehicle.) 

And there is no marijuana impairment test.  

“While current marijuana testing is likely effective at removing drivers who may work while impaired, it also likely removes drivers who previously used the drug but would not operate a truck while impaired,” ATRI concluded. “This fact has led to the removal of many thousands of drivers from the industry based solely on past marijuana use.” 

Looking for a better test

For that reason, the majority (65%) of carriers and drivers surveyed by ATRI have indicated they would prefer an industry-wide shift toward a test that indicates recent marijuana use (for example, the day before), instead of the current test that can identify earlier marijuana use. 

“Testing impaired individuals through a quantitative measurement – which has been key to combatting drunk driving – remains elusive in the case of marijuana. There is not even a definition or quantitative threshold for marijuana impairment,” ATRI’s study says. 

According to ATRI, while the industry’s current approach does support safety, it also proves to be inefficient when drivers who do not present a safety issue are removed from their duties. 

The institute is calling for a nationally recognized marijuana impairment tool, an accepted threshold that would indicate impairment, and further federal research into the drug’s impact on highway safety. 

Existing research indicates the drug affects driving-related cognitive skills, decision-making, and reaction times, and some data has identified an increase in non-fatal crashes and collisions after legalization. But ATRI wants further federal research into the issues to close the knowledge gaps. 

‘Potential disincentive’

Prohibiting marijuana use outright was identified as a “potential disincentive” for truckers to stay in the industry. But the report notes there’s still a debate about whether restrictions should be loosened or remain in place. Each choice would present challenges for the industry. 

If marijuana remains a federally prohibited drug, more drivers will be removed from their duties. Some will leave for other jobs where there is no mandatory testing. 

For example, over half of the truckers who were prohibited from driving because of failed drug tests between 2020 and 2022 have shown no desire to return to their trucking duties. 

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Krystyna Shchedrina is a reporter for Today's Trucking. She is a recent honors graduate of the journalism bachelor program at Humber College. Reach Krystyna at:

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  • Having worked with people who that product in construction. And also seen what the effects are on certain people in other trades and many homeless that use it
    I would says anyone who used that product because of lack of cheap testing if you are under the effects of the product. No should drive a truck over 10000lbs or heavy construction equipment who has used it the past 60, days

  • Better safe than sorry. You can’t drive impaired. Period! Truckers and all other drivers must never be allowed to drive under any substance influence whatsoever. If you can’t stay away from marijuana, drugs and alcohol, stay away from the trucks and find you an office job!!! We can’t allow you to hallucinate behind the wheels and endanger the lives of others! The federal law banning truckers from the use of drugs and marijuana will never change so let that sink in! Truckers can’t use marijuana/drugs or alcohol. Period!!!

    • Well Golly gee, if people wanna smoke Marijuana they shouldn’t be in or consider trucking. Geez I don’t undetstand peoples ideology about it. The key words are “impaired or under tge influence” as far as operating any motor vehicle.
      It’s simple but yet a lot of these certain indjudt don’t get it. Heck as far as I’m concerned any job/accusation that involves particularly forklifts (these are motorized vehicles just not on an open roadway) or any such occupation that requires concentration, dexterity abd cognitive thinking/reasoning should have mandatory drug testing. Heck this would include most day to day jobs wouldn’t it?
      Golly gee if your gonna smoke weed maybe you shouldn’t even be working, you just might be a workplace liability, OSHA wouldn’t like that nor a companies liability insurance if an employee got injured on the job while under the influence of a controlled substance. People need to wake the hell up take responsibility for your actions instead of placing blame on others or especially who’s paying your wages.

  • Before I got into trucking I smoked marijuana for medical reasons I was in a really bad car accident and I also suffered from really bad anxiety and depression because I found my brother hanging him self. I wanted a change in my life and trucking has seemed to be my calling. I love this industry and even though I’m looked at as low as the dirt I love providing. Being on the road gives me a piece of mind and I know I’m doing something to help others. I stopped smoking because I knew I couldn’t use & proceed in my passion. I would love to honestly after driving 10-11 hours and dealing with all that I deal with while driving take me a smoke break to ease my back pain and sleep better. My opinion is any & every drug and or alcohol affects each person different. Coffee can be dangerous but it’s perfectly fine if you use it to stay awake. I feel like as a professional driver we should have more freedom but at the same token held at a higher penalty if we were to indulge & cause harm. Have limits of course because you can get right off the road and get a drink take a 10 hour break maybe 9 after the drink & be perfectly fine. Then what about home time and all the things that now are infused with maijuana. I have a best friend who mother passed away and he was with family didn’t smoke but ate something that had thc infused he was off for a week came back and had a random and failed because of the thc and he only indulged that one time was put out of work got into sap program passed the first test but was still placed out of work until he paid & completed sap requirement. He’s back working now same company he just don’t eat at family events anymore. Again my opinion is we are professionals for the most part lol I’m not speaking for everyone I feel like I should be able to make a lot more decisions when it comes to my career but again also be held to a higher penalty if I was to do anything that harmed another individual.

  • Good riddens to impaired driving.
    Would one want a surgeon to operate on oneself having toted up in the past day?

    Pay more to clean drivers. More will follow.

    I operated a small placer mine. I hired a person that insisted to tot up every 2 hours. Claimed he could’nt think straight if not toting up. I asked him to get a 1.5″ wrench about 50 ft away. Twice on the way he called back what he was to get. And when he picked up a hammer and called back . “is this the wrench you wanted” I knew he was trouble and drove him to a bus pickup stop on the highway. Returned, picked up the wrench and worked safely for the rest of the season.

  • Its a problem for all the ones that used as a medication an the ones just because they have to have it, if u use it as a cream for pain it will eventually show in a test down the road a few days or months , they should be able to figure out if u actually consume it as a ointment cream for pain or u actually smoke it an that’s an issue they can’t resolve, but people find ways to screw the system so be aware because when people use ia cream for pain there’s the ones that would try to lie an actually smoke it so far that reason i would just stay away from it i never smoked or even though about it ,i seen people look really out of place after they smoked in long run it can make you lazy. I don’t think its any better for your brain in the long run .peace stay away from it i say???

  • Its like ppl who drive cars can smoke but not truck drivers a damn shame let them smoke they be stressed over the road and away from family they need to smoke sum times

  • Well, might be time to grow up and stop smoking weed. Grab a beer, or some scotch, instead. Don’t drink 24 hours before your shift, and you’re good. I’m a fuel delivery driver.

  • I agree that drug testing contributes to the driver shortage but only by a very small amount. The drivers that wont drug test are usually chronic users that believe that they drive just as good when they are high than when they are not! They should not be on the road anyways. They are a danger to all of us. If they say they dont need to smoke pot, then why dont they quit for a month to get tested? Smoking pot is more important to them then getting a job, they should not be driving and quit complaining about having to get tested to protect the rest of the people on the roads (including themselves). About 80% of the pot smokers I know or have known believe they can drive just as good stoned as when they are not. I dont care what you do on your own time, but when it endangers others (we have rights too) dont do it.

  • First off people are really dumbfounded about impairment, for first timers smoking it, yes you can feel the affects up to 2-3 days from it depending on what percentage the marijuana is….. how many MG you Intake. Day 1 you feel stoned out your mind day 2 morning you wake up you feel droggy/kinda tired/morning munchies day 3 you still feel kinda r
    Drowsy but you can do normal activities…

    For experienced smokers who typically smoke 3-4 bones of high quality THc can do daily activity’s and even drive better high than driving sober!!! Point blank. I have come from experience myself from the trucking industry, for example I was an experienced smoker! On the days I did not smoke I drove like shit almost wrecked a couple of times including almost backing into another driver at the truck stop…. I would have to do 3-4 pull ups maneuvering the truck trying to get it into a slot. Vs when I would hit my vape pen or do a .3 dab I would drive perfectly I would only had to pull up once felt more energetic less head fog then I was sober!

    You idiots really have no idea what the difference is from a first timer to intermediate to experienced is… first timers should not smoke and drive

    Intermediate drivers can drive under the influence but not recommended in a high volume traffic area maybe the backroads (definitely not in a semi truck)

    Experienced can drive anything anytime

    I used to smoke it right before I would start my 10 hour trip and smoke it about a hour before a weigh station so I knew my limits and when my eyes wouldn’t be glossy or even look high

    The reason I got popped is because my fake urine wasn’t up to temp (it had worked so many times before) just this time was different….

    In other words just keep your mouth shut unless you actually know what your talking about Karen’s

  • Alcohol is available at every block. It kills hundreds of people every single day in some form or fashion: vehicle accidents, health issues, drunken rages, etc, however it is 100% legal. Placing cannabis as a schedule 1 has only forced many into deep alcoholism. How many deaths a year surface from cannabis? Does alcohol not inhibit judgement, senses, perception, etc for HOURS/day(s) after consumption?? Of course it does. If something needs to be identified as a schedule 1, it needs to be alcohol. I DO believe there should be a testing process to determine intoxication/impairment for cannabis (just like alcohol) but it does not need to read for more than 12/24 hours prior to testing. Anybody that believes cannabis is dangerous after 12/24 hours of consumption just simply doesn’t have a clue and needs to be educated. However, I suppose losing skilled, experienced and conscientious drivers due to failed cannabis tests (in their off time and not while driving) is better than hiring inexperienced and unsafe drivers that are hazards to life, property and assets. Is this what I’m understanding in some of these comments? To answer your question, yes I support the complete legalization and declassification of cannabis. ALSO, I firmly support STRICT regulation, testing and consequences for use of pharmaceuticals, cocaine, meth, heroin, etc and ALCOHOL in all safety sensitive careers (not just commercial operators) since all mentioned actually do take lives daily unlike cannabis……

    I am a commercial operator who could be given any form of testing: urinalysis, hair follicle, blood, whatever at any time and would be 100% clean of any substances although, I think all testing listed is uncalled for and ridiculous when it comes to cannabis