Article is from 2014. And when it was discussed last time, I believe the conclusion that focusing on highway fatalities was cherry-picking to show the best possible outcome given all the changes in crime / accidents in the past year in Colorado.

Having another year of data would be necessary here to really have believable claims about the impact.

I'm pretty sure that the point of the article is merely to debunk the idea that marijuana legalisation will lead to a mob of stoned drivers careening around the roads of Colorado.

From the article:

> These figures in and of themselves only indicate that the roads are getting safer; they don’t suggest that pot had anything to do with it

This data says that fatalities slightly increased in 2014:

https://www.codot.gov/library/traffic/safety-crash-data/fata...

Yea, the data is cherry-picked. If I were to guess, we probably won't see statistically significant data clearly tied to legalization for a while.

Statistically significant for what question?

"Traffic fatalities are going to triple because of pot!" needs much less data than "traffic fatalities might increase slightly because of pot".

That's true. I think absurd claims are going to continue to be absurd. I don't think MOST people were expecting a drug-driven apocalypse.

http://www.tylervigen.com/spurious-correlations anyone ?

Correlation, causation, propaganda?

Is anyone claiming that Marijuana legalization caused the decrease in traffic accidents? From what I understand the anti-marijuana people were claiming traffic fatalities would rise, and this proves them wrong.

It's funny that the anti-marijuana people are screaming "correlation doesn't imply causation", but you know for sure they would be blaming marijuana as the cause had fatalities increased.

The article does not seem to be suggesting that marijuana has improved road safety (have you actually read it?)

> These figures in and of themselves only indicate that the roads are getting safer; they don’t suggest that pot had anything to do with it

The author is merely trying to put to rest the idea that marijuana legalisation => loads of stoned drivers causing accidents.

I don't even understand how these could be related, or how anyone could think these are related. Marijuana is known to make people drive worse. This is classic example of post hoc fallacy [0].

[0] https://en.wikipedia.org/wiki/Post_hoc_ergo_propter_hoc

It is actually known that musicians and athletes perform at elite levels while stoned.

The article only contains the 'post hoc' part, no 'propter hoc.'

This is common sense to anyone who has ever driven high on pot: you drive slower.

Common sense is often right but also often wrong, and I wouldn't expect it to do a good job at working out the nuance of whether you drive enough slower to counteract negative effects such as reduced reaction time, or other drivers expecting you to be driving differently (faster, for example, but also in more subtle ways.). And this particular common sense doesn't do anything to inform you as to overall driving patterns because it doesn't say anything about the percentage of people driving high, or about whether a significant number of drunk drivers are now stoned drivers, etc.

Agree 100%, I would not cite this common sense argument to shape our policy. However, I wouldn't be surprised if further study shows the reduced speed outweighs the negative effects in the balance.

I live in Colorado, and I don't use it, because of the "lingering" in the blood. I don't want to get high last weekend, get pulled over tomorrow in a speed trap, and get cited for pot in addition. It's ridiculous, but it is what it is.

EDIT: Plus the risk of an unrelated workplace accident and then testing positive and being fired, or refusing the test and being fired. A colleague was fired for testing positive a few years ago.

If you could detect porn viewing from a blood test, I wonder how many traffic fatalities would be porn related.

One possible reason for lower fatalities could be that some who've used pot don't drive at all for a period after using it. Not saying that's why, just playing "search for data."

Drunk drivers say literally the same about alcohol. Until you film them driving a car while drunk (or using a simulator) and then show them all the bits of their driving made worse by alcohol.

Would you dispute the claim that alcohol and marijuana intoxication manifest themselves in different ways?

1) The inebriating qualities of the two drugs are apples and oranges 2) The effects of alcohol on driving are well-documented, but do you have videos of stoned drivers driving poorly?

> do you have videos of stoned drivers driving poorly?

I don't even know many stoners who would flat-out make the claim they don't drive worse when high. Everyone I know hits a point of being high enough where attention is low, reflexes are slow, and/or you have physical symptoms (e.g. drowsiness). No, you're not exactly drunk—you are probably rational, aware, etc—but you also probably shouldn't be operating tons of high speed machinery at that point. Everyone makes mistakes, and you don't want to put yourself in a situation where your mistakes might kill somebody.

My recommendation is to ease off this tact as it comes off more like being in denial about your responsibility as a driver.

Absolutely you are correct that many marijuana users regularly achieve a high under which they ought not drive. One difference between weed and alcohol, is that the marijuana users are more likely to choose not to drive in this state, IE they don't suffer from the same critically impaired judgement that we often associate with drunk driving. IE they are more likely to be respectful of their responsibility as a driver than drivers that have been drinking.

> do you have videos of stoned drivers driving poorly?

Your claim is that your "common sense" is correct until proven wrong?

I realize I wasn't sufficiently clear. By invoking the phrase "common sense" I had intended to disclaim any notion that I had evidence to back up my opinion.

Something like this? http://www.cnn.com/2015/06/24/politics/marijuana-study-drive...

I would have suspected it was more to do with reducing driving while drunk more than it would be about increased driving while high.

But hey, I'll take the positive results where I can get 'em.

Or maybe just more people are getting high and deciding to bail on plans and just hang out on the couch.

...this is interesting, but it feels like there are so many possible factors involved that extracting meaning is difficult. Are accidents down? Are DUI arrests down? How are the numbers in neighbouring prohibitionist states comparing?

> Are accidents down?

Yeah, are people using pot really driving slow, per stereotype/anecdote?

EDIT: The assumption being that more low speed crashes carry fewer fatalities.

I think they also have new technology now because of the legality to actually test for certain levels of the psychoactive elements of pot in the blood, so maybe people are actually driving while high LESS (per user, not overall).

I suspect we're not going to see truly useful or significant data for years, if not decades.