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Comment by kdamken | Hacker News Reader

Do not read this and think it's okay to drive high. It's not. Do not drive high. Call an uber or something.

I worry that people read studies like this and suddenly justify going out and driving while impaired. Driving is an incredibly dangerous activity on its own. Doing it when you're stoned is a stupid and risky move, and comparing it to how much more dangerous drunk driving is doesn't make it less stupid.

If you've never smoked pot, you don't understand how it feels and affects your thinking/reactions/perception of time and reality. If you smoke pot everyday, it may affect you less due to tolerance, but it's still affecting you, much like a functional alcoholic.

I have nothing against usage and I strongly encourage legalization, but I don't think it's okay to pretend that it's safe to get high and go driving.

View on HN

It's also not safe to drive while tired, on any medication at all (including over the counter drugs), while texting, while on the phone, while not looking at the road, with glasses (they could fall off and you'd be blind), with a heart condition, etc etc.

I think it's safe to assume you drive very often with things that affect your driving. If pot is proven to not affect your driving to a measurable degree, then the only thing that is different between that and random over the counter medication is one is called pot.

People really, really shouldn't be driving under those conditions, either.

Yes, all those things affect your ability to drive. You shouldn't text and drive, but people do it, etc. I would say being stoned is a lot worse than the other things you listed though:

- When you're tired, you can have a cup of coffee and wake up a bit and regain some of that focus. You can't drink a red bull and suddenly be way less high.

- If you send a text or two while driving, you're not paying attention to the road for a few moments (which is admittedly still crazy dangerous). If you drive stoned - you're driving less safely the entire time you're driving. The combination of the two is even worse.

- Having a heart condition doesn't mean you're going to necessarily have a heart attack every time you drive - there's just a higher risk that something might happen. Even in that case, you may be able to stop/pull over. Once again, if you drive stoned - you're driving less safely the entire time you're driving.

- You can have a backup pair of glasses, you can pull over, etc.

But my main point - just because there are other things that can make the already insanely dangerous activity of driving more risky, doesn't make driving high less bad.

> - When you're tired, you can have a cup of coffee and wake up a bit and regain some of that focus. You can't drink a red bull and suddenly be way less high.

Actually, there are terpenes in cannabis that mitigate many of the confusing effects, which can be found in foods such as black peppercorns and pine nuts. Pliny the Elder wrote about this; see http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3165946/ So yes, there are ways to get "less high."

Not advocating that driving while high/texting/tired is a good idea, just trying to enlighten about some of the fascinating science behind Cannabis.

This is really interesting - thanks for the link. I'd be curious to see how effective that is in real life.

Stoned is ambiguous though. Nobody thinks it's ok to drive with a BAC of 0.4 but 0.04 is generally considered legal.

The question becomes what's Stoned? Detectable is not a reasonable limit nor is can't stand up.

> Nobody thinks it's ok to drive with a BAC of 0.4 but 0.04 is generally considered legal.

Not sure how you come to that conclusion. I think it's reasonable to assume it's legal because most people (including me) feel it's fine. I'm much more concerned about distracted driving generally.

A BAC of 0.04 is measurably impaired though. Mostly in terms of higher brain functions and reaction times making it both less obvious and often within a persons 'normal' range.

Something to remember is people generally drink late in the day. So, the accident statistics mix drinking and tired data. Tired driving makes things far worse, but it's hard to test for as accidents and being pulled over both tend to wake people up. Pot on the other hand is more often a daytime drug which is going to mess with the statistics.

BAC exists because a test exists to easily measure it. Breathalyzers aren't perfect, but they're good enough for government work.

I think an actual blood test is the only thing we got for MJ. That's invasive, and not likely something officers will be able to do at a traffic stop.

> Nobody thinks it's ok to drive with a BAC of 0.4 but 0.04 is generally considered legal.

Unfortunately, even 0.04 can get you arrested in California.

The BAC limit is simply when the DMV automatically pulls your license. You can be convicted of DWI/DUI at any BAC in California.

Now, you aren't likely to get pulled over at BAC less than 0.05, but if you do get pulled over, you can still get convicted for it.

> on any medication at all (including over the counter drugs)

I assume you mean any medication which may impair you.

There are lot's of medications which people should take before driving, like anti-seizure, antipsychotics, heart control, blood sugar control, and so on.

It will typically tell you on the label if it is safe to take and operate heavy machinery. Although I'd always suggest taking it the first time while not doing so regardless, just in case of an unexpected side effect or adverse reaction.

> There are lot's of medications which people should take before driving, like anti-seizure, antipsychotics, heart control, blood sugar control, and so on.

anxiety, depression, etc...

there's some overlap here, some people use cannabis to prevent/control seizures, to treat anxiety or depression, and don't feel side effects.

The experience of the common person who has tried cannabis once or twice and turned away isn't necessarily anything like the experience of someone who benefits from it.

You wouldn't say that a person with ADHD shouldn't drive on ADHD meds, but for anyone else, that would be effectively like driving on cocaine.

Some people should, in fact, not be driving while not under the influence of cannabis or another treatment for conditions that could make them unsafe drivers.

> You wouldn't say that a person with ADHD shouldn't drive on ADHD meds, but for anyone else, that would be effectively like driving on cocaine.

I thought it was pretty interesting actually, the big chart in the linked article suggests that stimulants actually lower the likelihood of an accident compared to a baseline.

I once had to drive myself few hundred kilometers back home after a discharge from a psych ward - i was taking some new variation of activisation pill intended to make me less apathetic. While usually I am super careful, will yield/brake preventively to avoid an accident (haven't had one yet - in big part thanks to mindfulness and survival instict) - in the begining that medicine just threw it out the window. I quite literally YOLO'd head on with an 18-wheeler because my brain just went OVERTAKE NOW, BITCH. (did not crash, it was just incredibly stupid and tight) Took me some time to adjust and stop being riddiculously reckless.

Same with nausea suppression pills for travel. I was once made to drive after taking one.

I'd venture to say that the lower likelyhood of an accident while on cocaine would come from most people that not pay any goddamn attention to anything, frantically scanning everything: the road, traffic, road shoulder, pedestrains, etc, etc

How did you "quite literally" have a crash that didn't happen?

I think emp_zealoth quite literally passed a vehicle while an oncoming semi was in the opposing lane. A "close call" if you will.

Stimulants have been shown to decrease your risk of accidents multiple times. Cannabis on the other hand has been shown to impair you ability to react, pay attention to multiple tasks, your metacognition... There's a huge difference here.

If you drive frequently, maybe cannabis isn't a good idea for you to take to manage your anxiety, depression, or seizure control. If there's not a drug out there that helps you that does not make you a danger to others, then tough shit, you shouldn't be driving.

Driving is not a right, driving is not something everyone should be able to do. I think I would be a sub par driver, and so I don't drive. I pay more money to live in the city close to public transit. I don't say "it will probably be ok" and endanger other drivers, and this would be especially true if I actually needed pot to function.

> Driving is not a right, driving is not something everyone should be able to do. I think I would be a sub par driver, and so I don't drive. I pay more money to live in the city close to public transit. I don't say "it will probably be ok" and endanger other drivers, and this would be especially true if I actually needed pot to function.

While it is true that driving is not a right, this is an extremely narrow view. Especially in small municipalities (0-80000 people) transit is often poor and/or nonexistent, and downtown/commercial areas rarely have residences built or even nearby. Everyone relies on driving. In fact, the highschool I'm from offered free drivers ed, as a part of highschool.

Everyone has to drive and few people are sub-par drivers.

People drive impaired [alcohol, painkillers, anger, phones, passengers, weather, radio, stressors] all the time. That's not the point. The point is how much do we allow people to drive impaired. In the case of BAC, 0.05-0.08 is a common tolerance. This is not "zero," as people seem to think. Yep. You can have a beer (or two) and still be well within legal limits.

I'm not a libertarian by any means but we have very strict penalties already for people who kill others in vehicle accidents. I want to see INFORMED legislation not "i'm too scared to drive so nobody should ever do it unless they are of a perfectly clear mind and the road conditions are perfect."

Not everyone has the luxury of ordering an uber or hopping on a train for a few minutes to get home.

If your lifestyle makes you a danger to others, then you need to change your lifestyle. If that implies moving to a large city, then that trumps your desire to remain in a small municipality.

I think that many people are sub-par drivers, and that's why you see the horrible rates of accidents that you do today.

The point is not penalizing the behavior after it's happened, it's deterring it before it does. Informed legislation already has a situation like this -- we don't care if alcoholics have a blood alcohol of .09 and can obviously function, if they're above that level of impairment, then they are arrested for driving under the influence. It's better to be too restrictive than to lenient when it comes to potential manslaughter.

> If your lifestyle makes you a danger to others, then you need to change your lifestyle. If that implies moving to a large city, then that trumps your desire to remain in a small municipality.

Sorry—desire? Some people may chose to live in small municipalities, some don't chose. Some are forced to by their way of life (e.g. consider the people who grow your food).

I don't live in a small municipality. I'm merely pointing out the fact that your way of life is merely one way of living and is totally ignorant of the reality of many other people's experiences.

You're very rarely forced to do anything in life. My family has been in small farm agriculture for multiple generations.

Coincidentally they don't smoke pot and drive, because they're not inconsiderate, life endangering assholes.

My point still stands, that if you choose to take treatment that impairs your ability to drive, then you shouldn't drive. If driving is important to you, you should choose other treatment if you can. If you can't, then you shouldn't drive.

> You're very rarely forced to do anything in life. My family has been in small farm agriculture for multiple generations.

> Coincidentally they don't smoke pot and drive, because they're not inconsiderate, life endangering assholes.

Then there's a good chance that they consume liquor and get behind the wheel instead. I know a lot of farmers, and this is a pretty universal truism.

Nobody is forcing anyone to do anything but people generally don't feel compelled to uproot their lives/livelihood because someone far away is trying to tell them what's good for them. Because especially in farm communities, drinking and driving is most likely to cause endangerment to yourself, not others. Not much to hit on grid roads.

If you have never taken ADHD stimulants before then you might experience a little bit of euphoria the first few days of stimulant therapy, due to lack of tolerance, but I doubt it would be an impairment to driving.

Source: I've been taking methamphetamine (prescribed) for ADHD for quite some time. I experienced a little euphoria the first week when I initially started treatment on amphetamines but it was nothing even close to what I would consider impairment.

Your analogy is terrible. Marijuana is not comparable to anything you can buy over the counter. Unless you chug a bottle of cough syrup and then drive, which is just as illegal as driving drunk or stoned.

Actually I think there are a lot of things over the counter that affect you more than marijuana.

Have you taken Dramamine (the regular drowsy version)? If I take 1 pill I can sort of keep awake but I wouldn't try to drive unless it was an emergency. Taking 2 pills makes me so drowsy that I would not drive safely by any chance.

Those are the recommended dosages by the way, so no need to consume the whole bottle or box of that like with cough syrup. And that's just one of the myriad of different things you can get over the counter that can easily impair your driving.

So yes, I think the analogy is right to a degree (like all analogies). Even though marijuana does definitely change the way you perceive things and thus driving might not be something recommended to do, the GP's point is that a lot of people already drive under the influence of a lot of other substances, some of them potentially much more dangerous than marijuana.

Obviously part of the problem is that different people will react differently to marijuana, so like stated elsewhere in the thread, a regular user (like a functional alcoholic) might be able to drive "ok" and have no accidents but someone that is trying it for the first time, getting a particularly potent batch and then trying to drive is going to increase the chances of an accident greatly.

That doesn't mean I condone being fucked up (with whatever) and driving, but the GP has a point in that we are already living in a world where people are driving and doing other dangerous things while under the influence of "stuff". That also explains partly why driving is so dangerous and why so many people die each year from a driving-related incident.

Edit: So maybe we shouldn't be single-ing out marijuana as "the" bad stuff that causes accidents while behind the wheel and take a more "big-picture" kind of view. One of the reasons why self-driving cars are a good idea.

Agreed. I'm a pretty big guy, and one Benadryl is like getting shot in the ass with a tranquilizer dart. (I think the dosage is "1-2".)

No way would I drive after that.

I don't really mess with cannabis any more, but I think that a lot of folks have strange ideas about how it affects people.

If my only experience with the drug were the first couple of times in college where we were taking bong hits, then yeah, I can see why people would be shocked that you could drive in that state. It took a me a couple of years before I discovered that most of the folks (especially the folks in their 50s - 60s I hang out with) really are just getting a little bit at a time.

It's possible (and I think for many long-term users, more normal) to have only enough to modify your mood and outlook on events without becoming glued-to-the-couch high.

Pro tip: there is also a difference between having a beer with dinner and chugging vodka shots all night long. :D

"Pro tip: there is also a difference between having a beer with dinner and chugging vodka shots all night long. :D"

True, which points to the fact that it would be useful to have a well-understood BAC-like scale for marijuana usage, especially as the drug becomes more and more legal to use.

Clearly there's a difference between having one beer and driving an hour later compared to getting behind the wheel while nearly passed-out drunk. Lots of people have a decent approximate sense of what 0.08 BAC is when it comes to alcohol consumption, but everyone who is "high" is just "high" without some sort of well-defined scale.

tolerance comes into account, which is why comparing driving on marijuana and driving on alcohol is akin to comparing apples and oranges.

they're entirely, exponentially, infinitely different.

As a mathematician, I'm going to have to go ahead and disagree with you on "exponentially" and "infinitely" there.

it's hyperbole, not science. fair enough, though.

I'm going to disagree here too. I've never been much of an alcohol drinker. I've probably had six standard drinks in the past year.

If I drank a six pack of beer right now I'd probably pass out, while some of the people I work with would still be able to drive quite well.

Something roughly equivalent applies to marijuana.

if you smoked a joint (or 6 joints, whatever) with no tolerance you'd probably just want to eat a twinky and have a nap instead of driving.

even if you didn't, your motor control wouldn't be nearly as impaired, nor would your mental faculty.

your judgement also wouldn't be as impaired as having a 6 pack of beer with no tolerance, making it even less likely you get behind the wheel while too intoxicated.

I'd call that a "false" equivalence, not a rough one.

Fair points, and I agree with the impaired judgement thing too, and you're right it is a false equivalence.

I'll be honest...

What I meant to say was, talking from experience: when I smoke six bongs of straight or strong mix, there's no way I should drive a car. Mostly because I'm too busy laughing or sleeping.

Whereas last time I drank half a bottle of spirits I woke in a strange bed and could see my car out the window and had no recollection of how it got there.

Alcohol is one hell of a drug.

> a well-understood BAC-like scale for marijuana usage, especially as the drug becomes more and more legal to use.

That'd be tough. BAC is a meaningful metric because alcohol crosses the blood-brain barrier very easily. So, the amount of alcohol in the bloodstream is a very good predictor of the amount of alcohol acting on the brain.

THC, on the other hand, does not cross the blood-brain barrier so readily. So the problem isn't that we can't measure the amount of THC in the blood; it's that it doesn't actually tell us anything meaningful[0].

> Lots of people have a decent approximate sense of what 0.08 BAC is when it comes to alcohol consumption, but everyone who is "high" is just "high" without some sort of well-defined scale.

I actually don't think it's true that most people have an approximate sense of what .08 is. I think that most people believe they do, but most people actually have a very flawed misunderstanding of what .08 means (and doesn't mean).

You can test this out yourself! If you want to be the life of the party, buy a portable breathalyzer for about $100. When you go out, ask your friends to guess what their own BAC is (and what their friends' BAC are, based on how drunk they're acting). I bet you you'll find really large disparities between the numbers. People just aren't very good at gauging how drunk they are (or how drunk their friends are). Or, alternatively, BAC just isn't a very good measure of impairment - you can interpret this either way.

[0] http://www.ncbi.nlm.nih.gov/pubmed/12404577

Unless you can easily estimate your BAC yourself, it's not useful.

There is also a world of difference between sativa and indica. Sativa dominant strains can often leave you very 'clear headed' and active while indicas more often than not make you, like you alluded, couchlocked.

> If pot is proven to not affect your driving to a measurable degree

What??

The very second sentence of the article reads:

"And after adjusting for age, gender, race and alcohol use, drivers who tested positive for marijuana were no more likely to crash than who had not used any drugs or alcohol prior to driving."

Edit: Just in case in the future anyone comes across my comment out of context of this thread, I'd like to add that without seeing further research I'm not personally convinced by that statement.

Since testing positive just means that you might have used anytime in the past month or so, that's not meaningful.

The study linked in the article confirms that yes, according to the evidence seen, marijuana significantly impairs driving ability, especially among casual users (to the surprise of no one whose actually used it I'm sure).

From the article

And after adjusting for age, gender, race and alcohol use, drivers who tested positive for marijuana were no more likely to crash than who had not used any drugs or alcohol prior to driving.

That's not what that means, though. All that says is that testing positive for marijuana doesn't provide a meaningful measurement of impairment. It does not mean pot doesn't impact your driving.

Everything impacts your driving, unless you can show that driving while high is an actual problem that needs solved (it isn't) then there's no justification for any laws about it.

You have to take into account that the population under study -- drivers who tested positive for marijuana -- are people who consumed some amount of marijuana AND judged themselves capable of driving. Some pot smokers will exclude themselves from this population because they estimate that they can no longer drive safely -- myself being one of them. So from this study you cannot conclude that, in general, smoking pot does not affect your driving skills.

Yes you can conclude that precisely because you don't lose the ability to know when you've had too much. Unlike alcohol, pot doesn't affect your ability to judge that.

I feel like you didn't even read the article. Here's the summary of the linked study:

> Differences in study designs frequently account for inconsistencies in results between studies. Participant-selection bias and confounding factors attenuate ostensible cannabis effects, but the association with MVA often retains significance. Evidence suggests recent smoking and/or blood THC concentrations 2-5 ng/mL are associated with substantial driving impairment, particularly in occasional smokers. Future cannabis-and-driving research should emphasize challenging tasks, such as divided attention, and include occasional and chronic daily cannabis smokers.

Suggesting that taking a couple Tylenol is as dangerous as smoking anything (even tobacco for occasional users) before/while driving is ridiculous.

I believe that comparison with an over-the-counter antihistamine, such as diphenhydramine (Benadryl, Dramamine), Fexofenadine (Allegra), or Cetirizine (Zyrtec) would be more appropriate. Some of the people that I know take drugs to treat their allergies far more often than analgesics for headaches.

Here is a thought experiment. You are a passenger in a car, chained to the seat. Would you rather the driver drink shots of ethanol, smoke marijuana cigarettes, swallow antihistamine pills, or log in to Twitter/Facebook via mobile phone? Assume that you wish to minimize both risk of death and the severity of nonfatal injuries.

Very good thought experiment. I would choose marijuana over any of the others in a heartbeat. The only exception would be if the driver is not a regular user. In that case, probably the antihistamines.

Cetirizine and fexofenadine (most 2G antihistamines, in fact) have no significant sedative effect.

Anecdotal, but I am very familiar with a counterexample. The sedative effect is not as severe or persistent as with a 1st-generation drug, but it still has a significant effect on this particular individual, if not a statistically significant effect on the general population.

That isn't what the article was saying.

I do find it a bit unfair to compare daily smokers to functional alcoholics, however - there is a definite difference in the way the drugs affect folks. This was the main point of the article. A slight buzz like that of a daily smoker - or someone using for medical reasons - isn't affecting safety, but going more than that and it should be obvious. Be safe and all that.

Besides. Part of the issue is that public transportation lacking in a lot of parts of the country. Some folks just don't have options, even things like Uber, and if you live just slightly out of the way, such things wind up costing even more money. If you are drunk, you can get arrested in some places (indiana) for walking home - instant public intoxication charge. Still more places don't have safe options to walk or ride bikes if you are impared. These things need fixed to be able to do what you are encouraging.

The key point in the article is actually the tests used. THC stays in the body long (days/weeks) after you're no longer impaired.

If a breathalyzer test on Tuesday picked up the beer you had last Saturday, there'd be no correlation between that test and accidents, either. (and no one would approve of using such a test for law enforcement).

> If a breathalyzer test on Tuesday picked up the beer you had last Saturday, there'd be no correlation between that test and accidents, either.

Not sure that's true: if the alcohol was still in your blood that long, it would still be affecting you and impairing function.

Yes, this is a key problem with the study. THC metabolites are cleared very slowly. Testing positive indicates that you used marijuana within a week or two. It doesn't mean that you're stoned.

For alcohol, a comparable test might look at long-term changes in liver biochemistry associated with alcohol consumption. In that case, there probably wouldn't be any correlation with accident rates.

Blood tests can directly measure THC. The article seems to be talking about such tests.

The problem is that there is not a well established mapping between THC levels and impairment. It isn't even clear if such a mapping can be done.

Maybe there's a key distinction between THC levels in the blood and bioavailable THC. THC is extremely lipophilic, so it might get trapped for degradation.

> These things need fixed to be able to do what you are encouraging.

Lack of transportation, other options or the public intoxication charges should not and cannot ever be an acceptable reason for driving while impaired.

If you indulge, don't drive. Period.

There is no option B. The only acceptable solution, if you have to get behind a wheel and drive, is to abstain from any impairing consumption.

>If you are drunk, you can get arrested in some places (indiana) for walking home - instant public intoxication charge.

If you're so drunk that you'd get pulled over as a pedestrian, then you most certainly should not be driving.

>Still more places don't have safe options to walk or ride bikes if you are impared. These things need fixed to be able to do what you are encouraging.

How about some personal responsibility? Society isn't responsible for enabling people's drinking. If you can't get home without driving, then don't drink (or if it's a long visit, have only one or two, at the beginning).

"If you're so drunk that you'd get pulled over as a pedestrian, then you most certainly should not be driving."

Or you could just be walking while black (or hispanic, etc.).

Are you really blaming racism for DUIs?

I think he's blaming racism for public intox.

No, I'm saying that you don't have to be visibly drunk to be stopped by police, especially if you're a minority.

I don't think you understand. If you are legally drunk - blow a .08 on the test - you can get a public intoxication charge. It is that simple.

All that takes is living out of town and walking down the main route to your house and someone stopping and smelling alcohol.

It is great to put that theoretical thing in place. But people do, occasionally, mess up. I rarely went to bars because of transportation - others, not so much. Alcohol impairs judgement as, and if the options aren't there and easy to use, it is more likely that folks will drive drunk.

The law in Indiana was adjusted in 2012.

http://sftlawyers.com/new-indiana-public-intoxication-law-go...

Cool. Been living out of the country for a few years, didn't know that :D Thanks muchly. I was always hopeful that my walking home wasn't interrupted by cops and took alternate routes at times. This should have been the case years ago.

Look, honestly most cops have better things to do than arrest a person walking home from a bar and not bothering anyone. Yeah public intoxication is a thing and there are a few dick cops who will, but for the most part you don't have to worry about it. The cops around here don't arrest for public intox or even weed possession anymore because they know it will get bargained down to a fine and maybe court supervision (though if you are causing other problems or being an asshole they might). This is firsthand from a local cop. They just have a lot more serious things to worry about.

> I worry that people read studies like this and suddenly justify going out and driving while impaired.

The keyword here is "impaired." It doesn't just have to involve drugs, being exhausted and attempting to drive is also very dangerous. Not just for you, but for everyone else on/near the road.

This is true, don't immediately after waking up, when very tired, etc..

It is nothing like functional alcoholism. Marijuana does not cause someone to become overconfident and make stupid decisions and take risks, and it doesn't cause any significant change in reaction time when used regularly. But, of course, a functional alcoholic would probably drive drunk slightly more safely than someone who rarely drinks. But the direct CNS effects of alcohol make alcohol a pretty direct safety risk in ways that marijuana is not.

Also, do you support the .08 legal limit for alcohol? That's about two drinks for most people. If you do, do you think Marijuana should be any different? Why could I have two drinks, but not two joints?

Agreed. I think the value of results like this is to challenge selection biases. I have family in Colorado where marijuana was recently legalized, an action I support despite never smoking it nor having desire to. They're worried about the legalization resulting in everyone driving high, and they constantly cite 1 incident where someone rear-ended a cop while high. It's illogical to take anything from a single incident simply because it was relevant enough to make headlines and ignore all the other different incidents that don't make headlines because there's nothing novel about them.

Statements like this one are baseless, unscientific, and fearmongering:

"Do not read this and think it's okay to drive high. It's not. Do not drive high."

MAYBE this is correct. But it is also possible that being stoned is benign compared to allergy medication, sleep apnea symptoms, general fatigue, texting while driving, and a hundred other causes of risk, enough to make it hard to distinguish driving while stoned as an seperable risk factor.

The downside of statements like this is that they perpetuate a fear-driven enforcement model that will cost many people thousands to tens of thousands of dollars for infractions that are not making anyone safer. And there are opportunists ready to enrich themselves on that basis.

You're incorrect and you're incorrectly equating pot to alcohol as if the effects were remotely similar, they are not.

> And after adjusting for age, gender, race and alcohol use, drivers who tested positive for marijuana were no more likely to crash than who had not used any drugs or alcohol prior to driving.

That means users who are too high to drive know it, and don't. It also means you can drive high as long as you're not too high without adversely affecting safety.

Pot is not alcohol, it does not belong in that mold and there's absolutely no reason to single it out of the multitude of other things that can impair driving. Alcohol is a special case precisely because it impairs your judgement.

> I worry that people read studies like this and suddenly justify going out and driving while impaired

I don't know about that, I think the people who want to do that will just find another excuse. Especially potheads, who seem to be unable to acknowledge that anything exists in this world that isn't helped by pot. Driving? probably better if you do while high. Seizures? Pot is now the only accepted option man. Broken back? Here have a pot brownie.

Well I can say for certain when I take certain allergy meds I know I can't drive for crap. So I usually stay in. And when at work I just deal with the allergies as is since I have a long commute home since the last time I tried driving on allergy meds made it hard to concentrate. So, I can imagine it's not much better driving high on pot.

The article didn't say that it's safe at all - just that the measurement of THC in the blood doesn't tell you if someone is impaired. If someone knows they are high, they're probably at much more risk than the people with THC in their blood discussed in the article.

Impaired has meaning, there might be different levels of impairment and that is what worries me most. People vastly over estimate their driving skills when sober.

Which by the way, you ever want to see just how good you are in reality, go do one of the racing related or defensive driving course. Ouch.

I disagree.

Most days when I get out of work the first thing I do is smoke with my Pax2 as I walk to my car.

I then drive home 'high'. I've done this most of my adult life. Smoking Pot and driving has zero negative effects on my driving. In fact, just as the article points out, I am more likely to drive more safely and take it easy.

Also, for what its worth, there are two types of strains - Sativa and Indica.

Indica is the type that knocks you out and makes you sit on the couch doing nothing; Sativa's, for me anyway, gives a focused, up buzz that makes me sharper and more alert.

I am a Sativa-only guy and for me smoking and then dealing with rush-hour traffic is how I prefer things. If you are saying people shouldn't smoke an indica heavy strain and then drive, I could see that argument but, in my experience, it's still safer than alcohol. But yes, generally, I would agree with that.

Sativa's though, no way, that just doesn't make sense based on my personal experience.

> but I don't think it's okay to pretend that it's safe to get high and go driving.

I agree, but I also think it's more nuanced than that. Sure, at the extremes you're totally right. Though take a daily smoker who doses themselves with a predictable and regular amount... that person is very likely not impaired, or at least not more impaired than somebody who's behind the wheel while they're tired.

I think the reality is very complicated... and that makes accurate laws really hard to create. It certainly is easier to just say "you can't have any THC in your body while you're driving"... but I don't agree with that and I don't have a better suggestion honestly.

Did you read the article? What facts are you even basing your claims on?

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