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Over 40% of deceased drivers in vehicle crashes test positive for THC: Study

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Re: Over 40% of deceased drivers in vehicle crashes test positive for THC: Study

#111

Post by squigz »

nobodyandproud wrote: post #100
Arainach wrote: post #70

Earlier quoted context omitted.

On the contrary: we should test for the actual issue (impairment) rather than an arbitrary number.

Blood test is a reliable indicator: https://www.americanbar.org/groups/judicial/resources/highwa...

That link doesn't appear to say that blood tests are reliable

Literally in the summary

> While blood alcohol content (BAC) level represents an accurate measurement of alcohol impairment, the presence of THC in a driver’s body has not been shown to be a predictable measure of cannabis impairment.

But further on

> Because THC in the blood can result from both recent as well as past use, impairment cannot be inferred from blood levels.

Re: Over 40% of deceased drivers in vehicle crashes test positive for THC: Study

#112

Post by nobodyandproud »

quickthrowman wrote: post #68
reactordev wrote: post #29

Just noting there’s a difference between THC in your system and THC in your blood. THC leaves the bloodstream after your high. Goes into fat cells and other areas to be broken down and processed (up to a month) later. Having it in the bloodstream after an accident means they were intoxicated at the time according to science. Whether their CB1 receptors were letting it through is another matter. I can smoke a lot of w…

> I can smoke a lot of weed and not “feel high” yet I would test off the charts on this test. > With marijuana it’s not. So until we have a valid method of testing if someone is “too stoned to drive” we have to push back on any attempt to classify marijuana users as ineligible to drive. I agree. As someone who regularly consumes 250mg of edibles daily at a minimum, I’m sure my levels would be off the charts on a cons…

There are individuals that have a high tolerance of alcohol.

Thankfully society didn’t make exceptions. Eventually.

I see THC taking the same, slow, tortured approach.

Re: Over 40% of deceased drivers in vehicle crashes test positive for THC: Study

#113

Post by Chris2048 »

watwut wrote: post #24
iLoveOncall wrote: post #10

Earlier quoted context omitted.

> It would give better context to a dead drivers testing positive for THC. No it wouldn't. People make those excuses because it's weed, but you would have never posted that on an article about alcohol.

It absolutely would. If 40% of people test positive for THC, then this would mean there is no effect. I find it unlikely 40% of people test positive for THC, but yes, it does matter.

> If 40% of people test positive for THC, then this would mean there is no effect

Can you explain what you mean by this?

Re: Over 40% of deceased drivers in vehicle crashes test positive for THC: Study

#114

Post by Youden »

tokai wrote: post #13

An issue with having the legal limit at ~2-5ng/ml is that it makes habitual users be over the limit if they have smoked recently or not.[0] Making the prohibition seem unserious to some, not about safety but about punitive control, and in turn making it matter less if you smoke and drive as you are taking the risk of getting into trouble in any case. The impairments of driving under the influence of alcohol have been…

There was a larger discussion in a previous thread on this topic: https://news.ycombinator.com/item?id=45494730

Since then, [0] has been published and I think it's worth at least a skim. Since it's quite recent the introduction summarizes some of the most recent research.

The things that jump out at me are:

- [0]: Habitual users with baseline concentrations above legal limits perform just as well as habitual users with baseline concentrations below the legal limit, indicating that for habitual users, the legal limit doesn't have any relation to impairement.

- [1]: A study in Canada analyzed crash reports and blood tests to look at the state of drivers responsible for accidents. While alcohol had a very clear and statistically-significant influence on the risk of a driver causing an accident, THC did not.

To steelman the idea that THC causes accidents, [0] only looks at habitual users with baseline levels of THC and [1] only looks at non-fatal injuries.

My conclusion right now is that the number of drivers in accidents with THC in their blood is going up because the number of people with THC in their blood is going up, not because drivers who use THC cause accidents.

The law's assumption that this level of THC is evidence of impairment seems to be invalid.

The law would be better off measuring impairment in some way and perhaps intensifying penalties when an impairment test fails and the user has THC concentration above some threshold.

[0]: https://academic.oup.com/clinchem/article/71/12/1225/8299832...

[1]: https://pubmed.ncbi.nlm.nih.gov/31106494/

Re: Over 40% of deceased drivers in vehicle crashes test positive for THC: Study

#115

Post by sallveburrpi »

mrj wrote: post #107
walletdrainer wrote: post #55

Earlier quoted context omitted.

Sure, but the problem isn’t whether or not a driver is impaired, but the degree to which they are impaired.

Well, it would be good for the rest of us on the road if people driving two tons of murder box are 0% impaired. I'm no angel but I have gotten more diligent... I'm just reacting to "the degree". The goal has to be zero degrees of impairment when a moment of inattention can kill. Also, my son was just hit by a driver while he was on a bike and in the bike lane. They claimed not to see him. He's fine thankfully but it'…

Zero degree of impairment is only possible if we don’t have access to 2 tons of murder box. I think the way cars dominate roads and our public spaces and how they are being used is inherently dangerous.

I know this is going to get downvoted by people who cant imagine an alternative but it’s possible all the same.

Re: Over 40% of deceased drivers in vehicle crashes test positive for THC: Study

#116

Post by Chris2048 »

kube-system wrote: post #36
witte wrote: post #15

This feels like we’re missing a dimension or threeve, the one that comes to mind immediately would be whether or not the deceased driver was at fault for the incident.

Yeah, drug use is also influenced by social and economic status, which also influences driving risks. People of lower socioeconomic status drive less safe cars on less safe roads for longer commutes. This is something valid to evaluate with a drug like THC which is detectable long after use. It would be nice to see the distribution of levels detected and not just the average.

> People of lower socioeconomic status drive less safe cars on less safe roads for longer commutes.

But can't you account for 'type of car', 'type of road', 'commute length' as direct variables pretty easily without dipping into social/economic backgrounds?

Re: Over 40% of deceased drivers in vehicle crashes test positive for THC: Study

#117

Post by thrill »

Someone wrote: post #87

> In a review of 246 deceased drivers, 41.9% tested positive for active THC in their blood, with an average level of 30.7 ng/mL — far exceeding most state impairment limits. That could mean they all had levels far exceeding most state impairment limits, but it also could mean most of them had trace levels, while a few had levels way above 30.7 ng/mL. So, it says fairly little. Also (FTA) “Researchers analyzed coroner…

“Finally, no mention is made on the levels of THC in the general population of those driving cars.”

How do you propose gathering that particular data?

Re: Over 40% of deceased drivers in vehicle crashes test positive for THC: Study

#118

Post by nobodyandproud »

squigz wrote: post #111
nobodyandproud wrote: post #100

Earlier quoted context omitted.

Blood test is a reliable indicator: https://www.americanbar.org/groups/judicial/resources/highwa...

That link doesn't appear to say that blood tests are reliable Literally in the summary > While blood alcohol content (BAC) level represents an accurate measurement of alcohol impairment, the presence of THC in a driver’s body has not been shown to be a predictable measure of cannabis impairment. But further on > Because THC in the blood can result from both recent as well as past use, impairment cannot be inferred fr…

That’s not the relevant bit. A blood test detects recent use of THC.

Which other, less invasive methods cannot. Like alcohol, impairment is highly individual and so we set a threshold.

Re: Over 40% of deceased drivers in vehicle crashes test positive for THC: Study

#119

Post by epistasis »

roughly wrote: post #109
bko wrote: post #79

Earlier quoted context omitted.

I think it's lawlessness overall. For instance, consider San Fransisco traffic citations. Went from around 11k in 2014-2015 steadily down and then fell off a cliff during covid but never recovered (around 1k in 2023). I remember the sad story of Eric Garner who was killed in 2014 while being arrested for selling loose cigarettes in Staten Island. Today, at least in NYC, you see people parked out in front of the same…

I think it’s underappreciated the degree to which police and LEO have started behaving like political actors. NYC cops decided to “strike on the job” when the city started changing its stance in the mid-2010s, and in the Bay the cops responded similarly to Prop 47 by effectively not prosecuting shoplifting and other minor crimes anymore. Similarly, the recall of Pamela Price started almost the moment she took office…

It's not entirely new! In 1975 during labor negotiations the police detonated a bomb on the mayor's yard, partially damaging the front door, and left a note saying "Don't threaten us":

https://cdnc.ucr.edu/?a=d&d=DS19750820.2.20

Since then, the SFPF have always had a culture of being above the law. The monopoly on legal violence thing can be taken a bit too far.

Re: Over 40% of deceased drivers in vehicle crashes test positive for THC: Study

#120

Post by solumunus »

markeroon wrote: post #108
Sparkle-san wrote: post #53

Earlier quoted context omitted.

Got any real sources? I've been a daily user for over 10 years and also have a spotless driving record.

If we're doing anecdotes I'm sure there are lots of drunk drivers with spotless records. I understand that you're taking issue with the idea of always being impaired, but the article indicates that there's a pretty clear association between having ingested THC and being in a car crash.

There’s also an association with having drank water and been in a car crash. This on its own can’t reasonably inform any opinions, more context is required.
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