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Alcohol breath tests are often unreliable (nytimes.com)
324 points by pseudolus 36 days ago | hide | past | web | favorite | 299 comments

I think we should replace this with a simple ability test. A smartphone "game" would do the trick. I don't care whether people are tired, drunk, high or what, I just care whether they are able to drive or not.

That sounds like yet another field sobriety test which will correlate imperfectly with driving ability.

I’m a bit upset the article didn’t go deeper on how ridiculous it is to test breath as a proxy for blood.

Not good enough for medical diagnosis/select treatment but somehow good enough to throw people in jail.

> Chemicals, including the ethanol in alcoholic drinks, absorb light to varying degrees.

I’d say they bend/refract light.

>Since his arrest, Mr. Mottor has maintained a clean driving record. He is still paying off the roughly $30,000 he accrued in fines, court fees and legal bills.

Wow..... this man was exonerated. Is the NYT pulling a fast one on me? Is this article not the whole story?

You want it to tell the whole story of justice in America and how people get royally fucked over even when they're judged not guilty?

I think it's time we develop chemical agnostic impairment tests. I don't really care whether someone is impaired because of alcohol, research chemicals, or just emotions & extreme sleep deprivation; I care whether they have their wits, judgment & reflexes up to par to safely drive a car. And we should be able to test for that directly.

Most people that get pinched for DUIs aren't toeing the line at .08, from my experience, they are way up, .10, .20.

If you think it's unlikely that people could function even close to normally at that blood alcohol level, let me assure you, it is possible, and there are more high-functioning alcoholics out there than you think.

I'm surprised that nobody else pointed out this.

In US breath analyzer, lie detectors, police officer's sworn statement have proven many times to be very unreliable.

And yet they are trusted again and again.

I'd prefer more direct mechanisms, but since it raises the cost of driving and at least temporarily bans some people from driving, I'm for it.

It seems that a lot of forensic "science" has been found to be pretty dubious recently.

Where I come from they have a blood test taken if you're caught drunk driving.

In NL you can always ask for a bloodtest if the breath test is positive.

In Denmark the breath test is only used, if positive, to force you to do a blood test.

So the actual problem is that they don't take blood tests after the breath test says u drunk? In Germany this must happen (unless u say u drunk I think)

In the UK if you fail a road-side test you'll be arrested and the police will conduct 2 further tests with another equipment as soon as you get to the police station. The lower reading of these two tests is kept.

Interestingly, Police cannot demand a road-side breath test without cause.

So police do no random road-side breath tests in the UK?

Almost every time I have done the breath test (ten times or so) it has been in checkpoint tests where a dozen officers breath test every single driver during a few hours.

In the UK they certainly do. There's usually a campaign around the christmas season. But it's carried out under the guise as a general vehicle checkpoint. When stopped the officer will speak to the driver and then if they have "good reason" to suspect you've been drinking can insist on a portable breathalyser test.

This reddit comment sums things up reasonably well:


That's not random testing since they have to establish cause, as that Reddit comment explains. Of course the Police may ask and many people will not know that they are not compelled to accept without cause, or they don't want to argue.

In some countries the police is allowed to conduct road-side tests without cause.

The roadside checks themselves are random as they aren't announced to the public, or if they are they're posted somewhere that's non-obvious. What comes afterwards when pulled over at one of these stops is inevitably a check to see if you've been drinking.

I'm not saying this is fair or in the spirit of the law, but it's how they do this, and they're random enough.

Yeah I can’t even see any good arguments such as for why police shouldn’t be able to breath test any driver.

>Maintaining machines is up to police departments that sometimes have shoddy standards and lack expertise.

So in court is this where you request calibration records and have your case thrown out? This was a tactic to also have speeding tickets thrown out- radar gun calibration records not kept or not done correctly.

I knew a Justice of the Peace and asked him about the radar gun calibration tactic. He said that it's bogus and in his 40 year career had never seen it work.

I have received dozens of speed camera tickets (a "work zone" trap that was active even when the work zone was de-posted, 100% of them were thrown out) and the cal info for the radar was included with the ticket, probably to save everyone time for trying to argue up that alley.

Winning in traffic court is like winning forced arbitration. There is no neutral jury, you have judge that is being payed by the same government who benefits from the fines. Speed traps are illegal in California yet i still see cops hiding in alleys or shooting lidar off overpasses. It’s worse in small cities where city cops sit at the transition of highway speeds to city speeds and catch inattentive drivers.

Judges aren't particularly motivated by fines. Unlike police officer, they don't get a cut or a bonus for collecting fines.

You have a position of power in a system. A position that gives you a good salary, power over your fellow citizens, recognition and social status. You're probably going to identify yourself with the system, and thus, some level of bias pro-system is very, very likely.

Judges that process traffic tickets don’t really have any of those things.

That’s what they say about forced arbitration. They are still appointed or hired by the municipal or county government. It beneficial for these governments to hire judges who will benefit them just like forced arbitration and companies.


Ha ha ha. The obvious solution is the best one, huh?

Here in New York there’s a road in Brooklyn called “Ocean Parkway”, which has grown notorious for crashes small and large. In recent years it’s been studded with speed cameras, which collectively have reduced the speed on this wide 6-lane thoroughfare to something very close to the prescribed 25 mph. Speed cameras really do work.

You know what’s even funnier? Those who are unaware of the cameras, or don’t care about those robofines, tend to look like complete idiots when they speed and swerve around rows and rows of cars driving nicely and carefully at 25 mph.

The reason for speed traps being banned is that they don’t help with road safety. What helps is cops being visible and patrolling the roads for dangerous drivers, not hiding in alleys or on overpasses.

Traffic enforcement should only be about safety and not revenue. But at as we saw red light cameras, cities places them at lights with the most traffic and not the most dangerous intersections. They lowered the yellow light times and in some cities it was so low that you couldn’t safely stop the car in time. Cities always try to skirt the rules to make more money and traffic court is a good example. Government shouldn’t be able to deprive people of property (money) without a jury trial.

Literally none of that matters if you don't exceed the speed limit.

There are a few sections of my commute where (IMO) it is more dangerous not to speed. The best example is I have to merge from the right, and get to the left-most lane for my exit, so I'm crossing over four lanes. The speed limit is 55, but pretty much everyone is driving at 70-80.

Sure, and no one is being pulled over in those situations.

Speed limits are chosen by governments. Ostensibly the purpose of speed limits is road safety. But when those choices are driven by perverse incentives, they can lead to less safe roads. A snarky dismissal isn’t warranted.

It absolutely is warranted, just stop going above the speed limit, and all your speed trap problems go away.

You're acting like you have no choice but to speed, but you do have a choice, you always can decide to go the speed limit.

Can confirm, I tried it, didn't work at all. The courts aren't stupid.

I'd argue that this means they are stupid. If the machines weren't properly calibrated then they can't be relied on to be accurate.

It turns out that radar guns are pretty accurate and don't really lose much calibration over time. They simply don't see widespread problems with misbehaving radar guns.

So when the court hears someone complaining about calibration or whatever, >99% of the time it's just trying to weasel out of a ticket on some technicality, and the person was legitimately speeding. The court would have to be stupid to fall for this ploy. Remember, the standard for traffic court violations is not "beyond a reasonable doubt", it's simple preponderance of evidence.

Worked for me in Virginia. Cop unable to produce current calibration led to discarding the citation

A lot of talk on these threads about the finer points of exactly how much alcohol is in the blood, and how different people respond.

The fact is, if you are driving, you should drink 0 (zero) alcohol. Arguing over the exact blood-fraction you can get away with, is missing the point.

In theory, sure. But many other things can affect a driver in ways that make them dangerous. Being tired has been demonstrated to affect people similarly to how alcohol affects people, but almost every single person driving to work is driving tired. That doesn't suggest we should allow people to drink and drive, but it does illustrate that an absolute hard line policy against having any alcohol in one's blood is a bit ridiculous given the other ways someone may be dangerous.

Same goes for a lot of medicines people take. Some medicines will specifically tell you not to drive, and other medicines may react with other medicines to make a driver dangerous (and the driver may not even know it).

I have a better solution: reduce the need for people to drive themselves around as much as possible (public transport).

Legally, 0 alcohol is not the required standard except in some cases for minors in some states.

Especially for a man who has more bodyweight, having a small amount of alcohol with food over a dinner or something should not be an issue and not cause significant impairment.

Admittedly a lot of people take this standard and don’t realize their drinking is actually in excess, especially with wine or stronger beers. There are those toy breathalyzers which you can buy from amazon and test it yourself, but most people don’t and I’m sure the calibration on those is far worse than the police ones.

According to NYT and other far left media, any test on a human being is not reliable, breath analyzer, lie detector, SAT, ACT, blood test etc.

NYT is no doubt to the far of you, but that doesn't make it far left. As someone on the real far left what they think of the NYT and you'll get an education.

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