Nearly Half of Drivers Killed in (ohio County) Crashes Had Thc in Their Blood
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A study found nearly half of drivers killed in crashes in an Ohio county had THC in their blood, sparking debate about the implications of this data and the challenges of measuring THC impairment.
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That isn't to say intoxicated driving isn't a problem. I'm sure that it is (and there may even be data on it I'm unaware of). How to address it without law enforcement having an easy to use immediate test like a breathalyzer for alcohol, I don't know. Driving high/drunk/buzzed on any intoxicating substance is reprehensible and should involve education, public messaging, law enforcement action, and further research into all the aspects of it.
But, headlines like these, IMHO, do more of a disservice than a benefit.
Hard to argue that's a small percentage.
Half of Americans have tried pot at least once: https://news.gallup.com/poll/509399/fully-half-americans-tri...
https://nida.nih.gov/news-events/news-releases/2024/08/canna...
Post mortem diffusion can happen, in either direction. Unless the individual died while smoking, there would have been ample opportunity for the drug to distribute within the bloodstream that could allow post mortem diffusion.
Unless the numbers I have for the blood stream decay rate are completely wrong a number as high as 30.7 seems like an extraordinary claim requiring extraordinary evidence.
I saw a rate of 46% of car crash fatalities are within 30 minutes of the moment of impact. Unless they are only considering the subset of immediate deaths, I would be very sceptical of their numbers.
The fact is that people are bad at estimating risks so they need to be told the facts.
That sounds like a miserable way to get around. Driving is the bees knees.
Here is a video (timestamped to the relevant content) of an expert explaining to Huberman why it is so difficult to assess impairment from blood levels.
https://www.youtube.com/watch?v=jouFvyRZntk&t=6072s
The study in TFA may just be finding that nearly half of drivers in Ohio are habitual cannabis users, or used cannabis in the past few days.
I mentally add, "... because we can't even test for it when we pull you over, so... please don't."
Thats not entirely true.
I knew 2 people who loved to drive high. Evidently it feels great (their words, not mine).
Now, being incapacitated or inebriated with any substance is illegal. Even prescription drugs. And basic roadside sobriety tests like "walk in straight line", can be an easy fail if you cant stand up.
Now weirdly, ive never heard of anyone ticketed or pulled for driving sick or very tired. Even though both of those conditions can also be just as dangerous.
In my state you're only required to submit to chemical testing, which the courts have ruled the little portable breathalizer machine isn't, and even if you refuse all they can do is suspend your license and then try to get a warrant.
Only a moron would not consent to it, lest they lose their license for a year regardless of the outcome of their DUI charge, since it's a separate charge that cannot be fought (you either did the FST or you didn't).
(Of course, every state is different, but I was just matching your matter-of-factness as incorrect-in-general as it was.)
It's "voluntary" in Germany as well both for alcohol and other drugs, but if you refuse it the cops can and will use every avenue they can to make your life absolutely fucking miserable, and there are a looooot of ways they can abuse.
Especially if you are in the proximity of a highway or important federal road, they can pull off the full "border control checkpoint" under Schengen laws.
They couldn't even find a doctor/nurse willing to execute it, and even better like 12 hours of 2 officer's time was wasted (before they gave up, LMAO) trying to execute it so they couldn't hassle anyone else.
No charges, and since I refused to even talk to the police they had nothing.
I'll take getting dragged to the station any day instead of just handing PC to them on a silver platter with some subjective test.
Norway used to have a blood alcohol threshold of zero, and if you had any, you were immediately shipped to Ilseng prison, no ifs or buts. Sadly they have abandoned this enlightened policy.
All drugs have a half-life in a body. Alcohol is no different.
Remind me again, when you're measuring a half-life, when the result is 0? Thats right, its a sum of an infinite series. Hard to say how many days/weeks/months before you measure an absolute 0.
Again, we've seen this form of zero tolerance again and again, and its always the wrong answer. Good on Norway to get rid of this terrible policy.
Best I can come up with is VR/videogames
1. Get crossfaded (cannabis and alcohol to do both drunk and high). Sit in comfy chair. Close eyes, imagine a roller coaster. Yeah, that works.
2. Get in car, PASSENGERS seat. Someone else not inebriated drives. Enjoy the ride!
3. You can do on the sly cannabis vapes before going on a roller coaster at a theme park. Obviously harder to do. Again, you get strapped in, and enjoy the ride.
I’d test positive and then say “Good luck proving I was intoxicated while driving!” and then the DA would refuse to file charges, because there is no way to prove that with THC if you refuse roadside tests.
Not a drop of booze or a single puff that night.
Two weeks. If used at any time in that past two weeks, THC can show up.
Imagine if we could detect a drink of alcohol two weeks later. Nearly every accident would be classified as having alcohol involved.
You might be surprised to know that only something like 50-60% of Americans drink alcohol at all.
> 10% of drinkers consume over half of all alcohol consumed in Australia
https://www.ias.org.uk/2024/01/23/10-of-drinkers-consume-ove...
It's so much more nuanced than that.
Unlike alcohol for example, there's no clear dose of THC where it can be concluded beyond a reasonable doubt that the person is impaired. A dose that might give a regular user a gentle buzz could render a first-time user completely stoned.
It's possible that these people were all incredibly stoned while driving but it's also possible that many drivers in Ohio are regular THC users and have such a high tolerance that their function is unimpaired.
And like always, there's the definite possibility of confounding factors, like reckless drivers also enjoying recreational drug use.
It's also important to note that the article's focus on legal limits is somewhat pointless. As there's no clear threshold above which one is impaired, the legal limits are somewhat arbitrary and are determined by other factors, like whether THC can be reliably tested at the given concentration.
Ultimately, as far as I can tell, the current state of things is that we're fairly certain that THC is able to impair driving ability but we have no idea how much THC is needed to do it or how impaired drivers become.
For a somewhat reputable source, the NHTSA did a report to Congress in 2017: https://www.nhtsa.gov/sites/nhtsa.gov/files/documents/812440...
> It's possible that these people were all incredibly stoned while driving but it's also possible that many drivers in Ohio are regular THC users and have such a high tolerance that their function is unimpaired.
Can't you make this same argument with alcohol?
> Ultimately, as far as I can tell, the current state of things is that we're fairly certain that THC is able to impair driving ability but we have no idea how much THC is needed to do it or how impaired drivers become.
So how exactly would you propose states move forward with allowing people to consume THC and operate vehicles (or not)? We apparently can't even tell if someone is impaired in a reliable way.
No because a once-daily user of THC will continue to test positive for 14+ days after quitting completely. For alcohol it's 6-12 hours. They are not comparable.
"Your honor, my client is a raging alcoholic. Yes he blew 0.2, and while that may make the average person highly intoxicated, my client can function perfectly well at that level."
Other commentators are pointing out and linking to sources that explain how the tolerance bio-mechanisms are very different between alcohol and marijuana. It's an apples-to-oranges comparison that happen to use the same word "tolerance."
> So how exactly would you propose states move forward with allowing people to consume THC and operate vehicles
And that is the conundrum, ain't it? At the very least, the HN crowd is saying "don't take an approach that works well for A but not for B, and apply it to B anyways because it's an easy thing that makes your re-election campaign look like you're doing something instead of having the difficult, nuanced discussion of what IS the right enforcement model for something new."
The risk is these things tend to get cemented in once they're passed. We already did that once with marijuana when we scheduled it more dangerous than methamphetamine, fentanyl, and diazepam. But hey, that scheduling sure did win Nixon the political points he was looking for...
Yes I've seen that but I have a HARD time believing that two or three beers affects an alcoholic the same as it affects someone who drinks once a month. Alcohol tolerance is also a thing, why are people suggesting it isn't?
> The risk is these things tend to get cemented in once they're passed.
Yes but, it sounds like you have to have some sort of test for this, lest it turns into an "officer discretion" kind of thing since there's no reliable way to measure intoxication. Otherwise, it basically sounds like you can get as high as you want and no one can possibly charge you with DUI because of "you can't prove how long ago I took it" or "I have a tolerance, it doesn't affect me" (which totally does not fly as an argument in court with alcohol).
End result is that worst reaction time is coupled with more risk taking and for many people with increased aggression. Making situation worst.
Well, It's like "functioning" in "high-functioning autism"; it's speaks to how well they can function in society, not how well they can operate a motor vehicle (nor anything to do with reaction times).
While it's true that alcoholics can perform most tasks better than the average person after a few drinks, and there is some data showing they are less likely to get in accidents after drinking, they still become significantly impaired at about the same rate as everyone else. They might have an advantage of a few drinks compared to a regular person, but they often close that gap. The amount of non-impaired alcoholics driving around with BACs above the legal limit is negligible.
The human body's ability to adapt to THC is far greater than its ability to adapt to alcohol. The Endocannabinoid system safely saturates, you can only have so much before the next dose doesn't really do much more. Alcohol, on the other hand, continues to have about the same marginal effect, until toxicity is reached.
This is completely self contradictory. It’s absolutely not “the same rate” if alcoholics can drink multiple additional drinks without showing impairment compared to nonalcoholics.
> They might have an advantage of a few drinks compared to a regular person, but they often close that gap.
This is kind of absurd. “Yeah, they can drink way more without impairment, but they’ll probably still drink to impairment.” This is borderline future crime.
I certainly don’t think we should allow alcoholics to drive with a higher BAC, mostly because the entire point of BAC is to make assessment more objective, but your logic is pretty tortured here.
The best way to think about tolerance to alcohol is buying a small constant headstart, while THC is better modeled as a difference of rates depending on tolerance. I think most people will find that model useful, and the numbers (BAC) support that as a rule of thumb calculation.
Somehow you disagree that my model is accurate enough, but also agree that a constant cutoff is a good heuristic for legal intoxication from alcohol.
> Somehow you disagree that my model is accurate enough, but also agree that a constant cutoff is a good heuristic for legal intoxication from alcohol.
It’s not that I think your model isn’t accurate enough. It’s that I think your model is not consistent. A few extra drinks is enough to go from just barely under .08 to .16. If an alcoholic can run nearly double the alcohol intake (and double the BAC) of a nonalcoholic I don’t agree that this is nearly the same.
I agree with the constant cutoff because a constant reasonable limit is easier to administer. Less subjectivity for law enforcement is a good thing. I would probably support for the same for THC. “But I consume so much that I have a really high tolerance!” Ok, that’s not everyone else’s problem to deal with. Don’t drink if you’re over the limit.
It’s very different than THC where a 10x tolerance is pretty normal for a new user vs a heavy user. Relative to alcohol, that would be .08 vs .80 which is like twice the lethal limit.
Thus it’s very hard to set limits because one persons residual use from 6 hours ago is enough to get another person stoned off their ass. I don’t really have solutions there though.
The THC thing is tough and I will leave it to experts and (more likely) politicians to hash it out. I’m not sure I want more reliance on field sobriety tests though. “His eyes were glassy and he was slurring. No, the camera can’t really capture the glassy eyes and don’t really pick up the slurring…”
Considering some of the scores I have seen from the local police I beg to disagree. They have caught people with so much alcohol in their blood that your average person would probably be in a comma.
And I think your position on THC is irrational and probably motivated by your emotions. I have smoked quite a bit and been around quite a lot of stoners, and they all think this way (oh, I'm used to it, no effect) but my experience tells me otherwise. It's the power of magical thinking, but even a regular user is quite impaired, right after the first joint. I personally have been able to test this, with a quite lower performance in video games, even though I felt I was doing quite good. Stats said otherwise. And I can assure you that I was quite a heavy user at that time, since my brother was growing the stuff and I was getting it for free basically.
In my experience most cannabis users are quite irrational around the stuff because they want it to be magically better than what it is. But in the end, it is no better than alcohol and, in some ways, much worse: the effects last longer, pushing into the next day, which is what I believe happens in those accidents. The users believe they are more in control than they really are and their reaction times are quite worse, which would be actually very easy to measure...
When the legal limit is 0.08 or lower, that's the difference between "too drunk for a non-alcoholic to drive" and "perfectly fine for an alcoholic", isn't it? Yet no court would accept that as an argument.
AFAIK the same isn’t true of alcohol - people who drink a lot may learn to be more functional while drunk, but I don’t believe that someone with a high tolerance has any faster of a reaction time than someone with a low tolerance, if their BACs are the same.
I'd like to point out that blood alcohol levels are not 1 to 1 connected to level of impairment, but still serve as a useful indicator for ability to drive. Those with high tolerances behave differently than those with lower tolerances. The current Cannabis test is far from perfect, but seems to be the best proxy we have available for empirical evidence of level of impairment.
Why do we need a "proxy?" What about good ol' field sobriety testing? https://en.wikipedia.org/wiki/Field_sobriety_testing
I'm pretty sure lawyers' advice is generally to say no when asked to take a field sobriety test, as you're basically only asked to do it if the police already think you're going to fail and therefore will be at minimum subconsciously biases towards expecting that. Much better to only let them do any breath/blood tests they can legally insist on. (At least, if you are indeed sober. I don't know what the best advice is if you're going to fail those tests, maybe in that case a tiny chance of being convincing with a field sobriety test is worth the chance?)
So until we have more research, we legislate to the case of the "first-time user completely stoned," no?
Throwing everyone under the bus because of the lowest common denominator is a shitty thing to do when we're talking $10k+ life altering fines here, but your attitude is how everything else involving driving is done so you'll probably get your way even if it's not moral or right.
INB4 people call me a stoner, haven't smoked weed in decades.
Do we agree that there is some level that effects everyone, even if that level is different? Do we require all THC users -- smoking, edibles, vaping, topicals, etc -- be tested to determine the level where they become impaired?
Speeding is speeding, causing a crash is causing a crash.
* THC threshold for a first-time user to register as "completely stoned": $foo
* THC level of someone who smoked the maximum amount they could 30 days ago, and hasn't smoked or eaten an edible since: $bar
Are you saying that $bar >= $foo?
Your argument is built on the supposition that there's a hard lower boundary on debilitating dosage. There is no such magic number, or it is nearly indistinguishable from zero.
We should simultaneously use this marker to prove drunk driving instead of the clearly outdated direct measurements.
They could not determine if people were high or tired but both were ineligible to drive according to their tests. Never heard of any improvements or applications.
Anecdotally I do think that it's more the case with THC than alcohol, but even with alcohol it's actually not so cut and dry. Two anecdotes from my life:
Me personally - when I learned to drive I was a very heavy drinker. Not "need to drink daily", but I certainly had weeks where I ended every day quite drunk. So when I started driving I bought an expensive personal breathalyser, that the company verifies calibration of before shipping and once per year after that, because while I wasn't looking to get behind the wheel right after drinking I was aware that I often drank enough to still be under the influence the next morning.
I learned that strangely, despite my having a very high tolerance for alcohol back then (like, able to drink a bottle of spirits or a few bottles of wine and still present socially as not impolitely drunk, just enjoyably buzzed), I would feel too drunk to drive before my breathalyser readings showed me above the UK limits. I verified with some disposable tests set at the (even lower) French limits, and I could pass them too while feeling too drunk to be safe driving, after ~5-8 units (a few pints of beer, or half to a whole bottle of wine). If I drank more than that then I would start blowing over the limit, but drinking that amount I would reliably be under the legal limit despite drinking enough that most people would show as way over the limit. I've no idea why, maybe my body is just weird, maybe it's related to how high a tolerance I had (though, like I said, I would be feeling too drunk to feel safe driving even if legal), or what...
Second anecdote is about the husband of a colleague I once had, back before I was a driver myself. I was at their house, we had been drinking together for a few hours, but wanted to get across town for... that's another story. So I said I'll call a taxi, but he claimed to be able to drive safely despite having had 6 or 7 large beers. I assumed it was drunken bravado and insisted no, but then his wife started backing him up and I had a lot of trust in her judgement. As it happens, a week earlier I had been at a televised esports event where all the players had been given a reaction times test using a custom built piece of software, and I had that on my laptop. So I sat him down with it, and fuck me if his reaction times while drunk weren't better than 90% of the professional gamers who'd taken the test. I still felt like I was probably making a stupid decision agreeing to get in the car with him after that, but honestly the journey was about the smoothest drive I've ever witnessed. I'm fairly sure he would have blown way over the limit if tested (unless he was weird like me, back when I knew him was before I learned about my breathalyser results), but if police had seen him drive, or talked to him, they would never have guessed he might be drunk except for the smell of beer on his breath. And it definitely wasn't just me being too drunk to realise he was driving dangerously, a couple more times in the future I got into his car sober while he has been drinking, and felt equally safe each time.
I've no idea what % of people are like me, and can be technically legal on the tests despite feeling too drunk to be safe, or like that man who could be way over the limit yet still drive safer than most sober drivers. But there's at least some people like that! Ultimately the legal limits (which let's not forget, vary from country to country) are a best effort to be a rule of thumb, they're not a perfect indicator of where the safe line is.
Edit to add: I'm sure there are far more people who drunkenly believe they can drive safely despite what they've drunk and are wrong, than there are people like that man who genuinely can drive safely having drunk a fair bit. It's very common for alcohol to give people false confidence, so please don't use my anecdote to justify drunkenly deciding to drive.
If you are drunk, high, tired af, or just sleepy, stop being a danger for others. A car is a hunk of metal going at high speed, stop being a child about it.
How many recently dead Ohio adults have THC in their blood? Forget driving.
Granted not a lot of the deceased are going to get these autopsys though.
Still, a good control group
This is trade-off that any rational person could predict.
Except that's not at all what happened, something mentioned multiple times in the article.
> No Effect from Legalization: The rate of drivers who tested positive for THC did not change significantly before or after legalization (42.1% vs. 45.2%), indicating that legal status did not influence the behavior of those who chose to drive after use.
https://en.wikipedia.org/wiki/Contaminated_currency
I wonder because it might be many people have THC in their blood for days, and it might not indicate what the prosecution infers. (I think thc lasts longer than say alcohol)
Perhaps it’s time to start treating motor vehicle operation as an actual privilege rather than a “right” gated by a far-too-easy licensing regime. Start by tasking safety officers with more citations for things like failing to signal or illegal turns through dash camera footage (to avoid dangerous traffic stops), start suspending licenses earlier for consistent or serious infractions, and raise licensing standards higher to shunt more folks onto smaller vehicles or public transit.
This isn’t a cannabis vs alcohol debate despite the framing as such: it’s a debate over how many people should be allowed to drive at all, and to what degree we hold them accountable to ensure good behavior.
Ohio recently passed a marijuana decriminalization bill.
On the other hand, Amish communities had glass-smooth roads and people were careful when passing horse carriages.
They’re basically saying in a random sampling of dead people 50% had consumed THC at some point in the last few weeks.
So this is more an analysis of THC use in the population and in no way can be causally linked to the deaths.