
Alcohol breath tests are often unreliable - pseudolus
https://www.nytimes.com/2019/11/03/business/drunk-driving-breathalyzer.html
======
todd8
I was selected for jury duty on a DUI case. Interestingly, there was also a
lawyer selected. After hearing the case we were all moved to a room to
deliberate.

After electing the lawyer as foreman, we proceeded with a preliminary vote on
how we felt about the case presented. Only two people voted not-guilty, me and
the lawyer. I discovered that the average person on a jury has a great deal of
trouble with evidence. It was really quite troubling. For example, one person
said “I’m a parent and so I vote guilty because I’m really against drunk
driving.”, what sort of reasoning is that?

In the end, we acquitted the defendant. She was arrested after pulling out of
a bar’s parking lot (because she spun her tires on the gravel as she pulled
onto the street ??). The arresting officer took her downtown to be tested. She
passed the videoed sobriety test there (walking a triangle marked path
backwards while counting or saying the alphabet, etc.) In the jury room we all
found the test quite difficult when we tried it, she did it perfectly.

She blew right on the line, .08 if I recall, but it was one hour after leaving
the bar before she took the test. So her blood alcohol could have been higher
or lower when she was arrested depending on the timing of her last drink. The
lab tech was unable to describe the accuracy of the machine and clearly had a
pat description of the subject taking the test that was designed to validate
their guilt. Likewise the arresting officer wasn’t very believable and had his
Mom in the car with him (?).

~~~
blunte
What you described, with "what sort of reasoning is that?" is the mechanism by
which marketers (especially those marketing politics) use to steer simple
minded people with. Unfortunately, most people are simple minded and are
unable to separate their emotions from reason.

~~~
traderjane
Where does that leave our democracy?

~~~
prawn
You might find this piece interesting if you haven't already come across it:

[https://www.politico.com/magazine/story/2019/09/08/shawn-
ros...](https://www.politico.com/magazine/story/2019/09/08/shawn-rosenberg-
democracy-228045)

------
flowersjeff
I was recently called in for jury duty, as a Professor in the physical
sciences - I'm rarely selected (although I love being on them.) The person
next to me was an MD.

Well the question was asked of both of us, (paraphrasing): "is a lab report
the end of the conversion for you?" The MD basically was a 'yeah, why would a
lab tech lie?' (very true - having been in industry myself). However, I know
how many ways something could yield poor results and must look at the whole
picture.

Whilst it is true that lab techs are not paid well enough to lie. Lab techs
are not paid well at all, and so this doesn't necessary attract the best of
the best. I've seen folks operating instruments that they had zero training on
(as it was assumed that they saw it in school - not a good assumption of
late.) Eg: One team I was an auditor for, didn't realize that the instrument
they were using had effectively two (2x) ON/OFF switches - and the detector
was turned off. 2 years of data had to be rejected.

Now imagine a completely untrained cop with a black box, that's been bouncing
around in their trunk - what could go wrong?... /s

I guess what I'm saying: field tests are highly suspect, and even lab tests
need to be carefully considered - all of which requires a solid grasp on
scientific/critical reasoning (which is in short supply.)

~~~
klenwell
You reminded me of an interaction I had recently while getting my blood taken
at a Quest office. To make small talk while I was sitting there in a chair
waiting for the needle, I asked the tech if he had heard about Theranos or
Elizabeth Holmes. He had not.

I explained that she ran a Silicon Valley startup that was trying shrink this
little cubicle area we're in here down to the size of an ipad.

I thought he might identify with the difficulty if not absurdity of that
mission. His response surprised me:

"Good idea."

"Well, actually, it turned out to be a giant fraud. She's been indicted and is
awaiting trial."

"Not surprised. You know how much money this industry is worth? Big Blood
isn't going to let that happen."

I let him focus on his work after that.

~~~
fma
There was one time I went I for a physical from a "doc in a box". I was new in
town and needed a physical to get some money for my HSA before a deadline.

I drank water before going in for my urine test. I never did a urine test...
And remember vividly peeing in the waiting room as I left, thinking it's weird
I didn't do a urine test. But I didn't care as it was through away results, I
just needed a formed sign for my money.

Well, somehow I got results back for a urine test. When I questioned it...
They said, nah no way its wrong... I did a test.

~~~
appleflaxen
that could easily be fraud. you should report things like this to your
insurance company.

------
varelse
I remember watching an anti-alcohol video in high school wherein they gave 4
or 5 people one drink after another and had them drive an obstacle course
increasingly intoxicated.

All but one of them got worse with additional alcohol, but the last guy, who
was probably a high-functioning alcoholic who drank daily, continued to drive
faster and more precisely with each additional drink well past the legal limit
until his skills collapsed catastrophically at around twice the legal limit.

So basically, I suspect it's hard to come up with a uniform standard here so
they err excessively on the side of caution and use a limit where an otherwise
teetotaler would be impaired. Finding out not even that is accurate is not
encouraging.

~~~
smileysteve
Another anecdote of SCCA Solo 1 racers at a GoKart closed course;

0 drinks, average times

1 drink, better lines, quicker times

2 drinks, horrible lines, sloppy corners, slower times.

~~~
rhcom2
Also known as the "Ballmer Peak"

[https://xkcd.com/323/](https://xkcd.com/323/)

------
tyfon
At least in Norway these are only used as an indicator not evidence, they take
the suspected drunk into custody and draw a blood test. If the test show no
alcohol then the person is released.

None of these field tests are accurate, not for alcohol nor drugs.

~~~
projektfu
In the US there are usually two separate offenses, one being driving
intoxicated as evidenced by your actions and failing a field sobriety test.
The other is being over the limit on BAC. There’s a third violation, refusing
a blood or breathalyzer test, that results in immediate suspension of the
license, but it’s not a felony. In some states like NY there’s also a
misdemeanor, driving with ability impaired, for those with BAC between 0.04
and 0.08. In most states these are all prima facie evidence of a crime.

~~~
loeg
In some (many?) states, you can request a blood draw in lieu of field
breathalyzer (without losing your license). It's usually the better option in
that situation.

~~~
projektfu
I think that’s right, that the only one you risk your license for is the one
at the station.

------
cascom
Just to be clear - the machines referenced in the article are the larger more
precise machines at police stations rather than the field test units.

As an aside - I think geography/access to alternative transport needs to be
taken into consideration, if you live in SF or NYC there is no excuse getting
behind the wheel after a few drinks - if you live in west Texas or Montana
these laws make it almost impossible to drink in a social setting legally

~~~
zamadatix
What has access to alternative transport got to do with whether you're safely
able to operate a vehicle? The law isn't about how much you're inconvenienced
it's about how intoxicated you are.

~~~
HarryHirsch
Normalization of deviance. When everyone else drives drunk it's no big deal if
you do it, too.

It's easy to lose sight of the problem. The goal is not to catch drunk
drivers, what we want is safe roads.

~~~
crankylinuxuser
Well, once we have automatic driving cars, drinking/drunk driving simply won't
matter.

It's one of those first derivative effects of automatic vehicles.

(edit: uh, seriously, -1's? How is this contentious at all? It's a matter of
fact that a drunk person has no bearing on safety with a automatic car. Sigh,
HN.)

~~~
nitrogen
My guess is that self-driving cars are basically a meme at this point and that
people believed a self-driving thread would detract from the discussion.

------
gengelbro
Recently spent a night in jail after having a single solitary drink. I suspect
(blood results outstanding) that the officer misread .019 for 0.19, which is
staggeringly high for a single drink, perhaps impossible.

Having that experience has completely collapsed my faith in the justice system
and worst yet, it has taken more than a month for the results and I'm still
waiting. My only mistake was being honest with the officer and offering that I
had had a single drink an hour before.

~~~
bdcravens
> offering that I had had a single drink an hour before

They teach them to multiple the number that people admit to by 2 or 3x.

------
Mountain_Skies
Another thing to keep in mind is in some states there are multiple DUI
statutes. In Georgia you can be charged with DUI Per Se for being over 0.08%
BAC but you can also be charged with DUI Less Safe, where even if you're under
the BAC limit, you can be charged for being a less safe driver due to the
effects of alcohol.

~~~
leesalminen
In Colorado there’s DWAI (driving while ability impaired) for 0.05, DUI for
0.08 and Aggravated DUI for 0.17.

~~~
smnrchrds
That sounds somewhat similar to Canada. In Canada, criminal code is solely
within federal jurisdiction, but driving is within provincial jurisdiction. A
BAC of 0.08 and higher is criminal DUI. But in many (most?) provinces, a BAC
of 0.05 and higher can lead to fines, losing your license, etc. It is not a
criminal offence, but it is still a civil infraction.

~~~
umanwizard
For what it’s worth, the US is not like Canada in this respect: each US state
has its own criminal code.

------
fencepost
Maybe I don't understand the difficulties faced by the manufacturers of these
machines, but for the price they're presumably able to charge there's no
justification for sloppy or incomplete code.

~~~
flyGuyOnTheSly
The article mentions that police precincts are in charge of keeping the
machines calibrated, which they often fail to do.

But it looks like programming errors abound as well... Yeesh!

~~~
milkytron
User error.

------
crankylinuxuser
In Indiana, if I'm asked by a cop, I am legally required to take the bullshit
test.

If I take and 'blows drunk' then it can up to a 180 day drivers license
suspension.

If I refuse, its a 360 day license suspension.

(And yes, every state is very different on handling and assumption of guilt.)

~~~
aidenn0
IANAL, but I'm pretty sure they need probable cause in IN to compel you to
take a breathalyzer. This is usually established with a field sobriety test.
Source: cops I've talked to in IN, who may or may not be right.

~~~
crankylinuxuser
I live in a college down (Bloomington). And driving a motor vehicle is NOT a
requirement for Indiana's drunk driving laws.

College students have been field sobriet'd on those damned Lime and Bird
scooters, found they exceeded the legal limit, and then were found guilty for
DUI. And unlike cars and boats, these things have no license. Doesn't matter.

Indiana's laws are fucked up.

~~~
aidenn0
Did you respond to the wrong comment? I didn't say anything about a car being
required.

In Indiana, any self-propelled vehicle is considered a "motor vehicle" which
obviously includes those scooters. I don't know if bicycles are included under
the OWI laws (many states a DUI/OWI is operating any "vehicle" not any "motor
vehicle."

------
brentis
As someone who had my run-ins... i was usually pulled over for speeding, then
a couple of times I was taken to he police station for refusal to do field
sobriety tests. The trick to beating these breathalyzers is burping audibly
prior to taking the test. This mandates a 30min wait to clear the alcohol from
your mouth. Do this a couple times and youve just burned off one drink.

YMMV.

~~~
MereInterest
While all your statements are true, your last sentence makes the entire post
be abhorrent. Raising awareness on the inaccuracy of breathalyzers is good.
Using this to encourage people to drink then drive, and framing the
instructions in that manner, is morally irresponsible.

If you drink, don't drive.

~~~
leetcrew
first, I'm skeptical that this trick actually works. IANAL, but as I
understand it, the police can extrapolate backwards from the breathalyzer
reading to estimate what your BAC was while you were actually driving. this
practice is somewhat controversial because different people have different
elimination rates, but I believe it is still generally accepted by courts in
the US. so unless you're able to delay to the point where you have a BAC of
zero (which can't be extrapolated from), this doesn't actually help you. it
may even hurt you by adding more variance to the situation.

second, GP did not go so far as to actually encourage people to drive drunk.
they merely gave (somewhat dubious) advice to anyone who may find themselves
arrested on suspicion of DUI. in almost any interaction a citizen has with law
enforcement, there is a strong information asymmetry working against them, and
not all officers are seeking a just outcome. imo, any knowledge or technique
that counters this imbalance is good for citizens to have.

~~~
owenmarshall
In many states this isn’t a “trick”: a 20 minute observation period is
codified in law before the evidentiary breath test is used to ensure that the
test is accurate.

See for example this publication from the Wisconsin bar association -
[https://www.wisbar.org/newspublications/wisconsinlawyer/page...](https://www.wisbar.org/newspublications/wisconsinlawyer/pages/article.aspx?Volume=88&Issue=1&ArticleID=23792)

> The protocol for an Intoximeter test, by contrast, is much more involved. A
> valid test on the Intoximeter must be preceded by a 20-minute observation
> period (to ensure the subject does not burp, belch, regurgitate, and so on).

Additionally I would be surprised if you can produce case law around
estimation and extrapolation of BAC being legally acceptable in courts: in
most cases the opposite is true. For example, Romano v. Kimmelman:

> In drunk driving prosecutions a substantial burden of proof to establish the
> competence or admissibility of the results of the breathalyzer test is
> appropriate because of the serious consequences of the breathalyzer reading
> in such prosecutions.

In general the best advice for people pulled over by the police is to refuse
any preliminary breath test and refuse any field sobriety tests. Those tests
exist to establish probable cause to take you to the police station for an
evidentiary test. Your state law may of course vary but in mine refusal of
either roadside test _is not_ illegal and the refusal is not admissible in
court.

If you are taken to the police station for a test because the police have
probable cause you almost certainly cannot refuse that test without violating
state law; this is where a good lawyer challenging probable cause for the
stop/search and the testing procedures comes into play.

------
matheusmoreira
Of course. It is a high sensibility field test designed to rule out suspects.
False positives are likely. The only thing it is good for is screening
suspects for further specific testing. Same goes for other drug tests which
can and do react to random substances.

The problem is people get jailed or fined based on the result even though it
proves nothing.

~~~
cascom
I think the article is in reference to the more sophisticated stationary
breathalyzer at the police station

------
ds
Ive always been curious and it seems like nobody really answers the question,
perhaps because the act of driving drunk is so faux pas:

If you know that you are drunk and you are pulled over, is it better to refuse
the breath test or not?

The only advice I have ever heard which made sense didnt answer that question
but suggested you stall as long as possible so that the maximum amount of time
would go by before you take the 'official' test at the police station, which
should in theory result in a lower blood alcohol percent.

~~~
mnm1
In all states I'm familiar with it's better to fail the test rather than
decline as the penalties for declining are much harsher, often twice as harsh.

~~~
pnw_hazor
Good advice unless a conviction will ruin your life.

For some people, a criminal conviction may be a far worse result than having
an administrative 12-month driver's license suspension.

I recall hearing about a local sheriff/police-chief refusing to do a BAC test
after an arrest for DUI. It resulted in an acquittal for lack of evidence.

~~~
Scoundreller
Refusing a breath test may be a criminal conviction itself.

At least it is across Canada.

~~~
javagram
It varies state-by-state in the USA whether that’s the case, there’s a
patchwork of state laws and one’s best bet is to consult an attorney familiar
with your state here.

(Please don’t drive drunk so you don’t have to make this decision!)

------
flyGuyOnTheSly
A friend of mine was let off of what was certain to be a drunk driving offense
because both officers who arrived on scene "forgot" the breathalyzer unit and
were too embarrassed to go back to the precinct and pick it up essentially.

So based on that anecdoctal evidence, I would guess that they are mostly
extremely out of calibration.

(If they're just these weird machines that nobody keeps track of or knows
where they are at all times)

------
sjg007
Breathalyzers should be regulated by the FDA or thrown out entirely. A blood
test is regulated and therefore should be realible. Right now Breathalyzers
are 510(K) exempt... this is clearly untenable.

------
lettergram
if I recall, you can refuse to take it. They then take you to a station for a
blood test (may need a warrant).

Depends largely on state though, but armed with this reporting you can
probably sue if you face consequences of refusing (implied Consent doesn’t
ring as valid if the test is not valid). Not a lawyer though...

[https://dui.findlaw.com/dui-arrests/can-i-refuse-a-
breathaly...](https://dui.findlaw.com/dui-arrests/can-i-refuse-a-breathalyzer-
test-.html)

~~~
lb1lf
As you say, it depends on your jurisdiction. In Norway, if you refuse to take
a breathalyzer test you'll have a blood sample taken whether you like it or
not.

Additionally, if you do consent to a breathalyzer test and it shows traces of
alcohol, a blood sample is taken to determine the exact BAC (And, presumably,
also to be used as evidence.)

~~~
Spare_account
>you'll have a blood sample taken whether you like it or not.

Are you saying they can forcibly take blood without your consent?

In the UK it's my understanding that you can refuse all testing but if you do
that you will be charged with a separate offence which has similar penalties
to the drink driving offence you're trying to wriggle out of.

~~~
egdod
In the US they can forcibly draw blood with a warrant. I don’t _think_ they
can without a warrant, but I’m not 100% sure.

------
jeffdavis
I think what's missing is any sense of perspective or judgement in the laws.

Driving drunk 100 miles an hour the wrong way when kids are going to school in
the morning is different than driving 40 on major roads after having a
cocktail or two with dinner. Yet the law basically treats the latter like the
former.

~~~
EvanAnderson
I don't want much judgement in the laws. If someone has ingested alcohol and
it's not yet metabolized I don't want them driving. It's irresponsible, full
stop. (Same goes for other driving impairments-- drowsy, under the influence
of drugs, distracted, etc.) The idea that one should be making a judgement
call on their degree of impairment and choosing to drive is odious to me. If
you're impaired, don't drive.

Edit: I'm not a molecular biologist. Let's edit this to say "If someone has
ingested alcohol and it's not yet metabolized to the extent that it is unable
to create a discernable impairment I don't want them driving."

Edit 2: It sounds like an objective test for reflexes and response time would
be a better test of impairment (of any type) rather than using blood/breath
alcohol measurements as a proxy for impairment.

~~~
jeffdavis
Drowsy driving causes more deaths than drunk driving plus drugged driving
combined. Ever driven on less than a solid 8 hours?

See _Why we Sleep_ by Matthew Walker.

~~~
EvanAnderson
Drowsy driving should be as much of a crime as drunk driving-- absolutely.
There is no excuse for getting behind the wheel impaired and exposing innocent
people to unnecessary risk.

~~~
hanniabu
This basically means that no night shift worker is allowed to drive home from
work.

~~~
gowld
Night-shift workers should sleep during the day.

~~~
hanniabu
My guess is you've never worked night shift. It's not as easy to sleep during
the day as it is at night, even with black out curtain, unless you wanted to
get drugged up every day.

~~~
astura
YMMV, I guess, I slept perfectly fine when I worked the night shift. (Went to
bed around 5-6am)

~~~
hanniabu
That may have been the difference. We didn't get out until 9am (12hr shift)
and by then the sun is high and bright so by the time you've driven home
you've spent enough time outside where your body has switched from "I'm tired
lets go to bed" to "the day is just getting started".

------
arnoooooo
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.

~~~
mc3
That sounds like yet another field sobriety test which will correlate
imperfectly with driving ability.

------
Scoundreller
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.

------
ouid
>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?

~~~
mnm1
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?

------
00N8
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.

------
thrower123
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.

------
eeZah7Ux
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.

------
mlinksva
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.

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

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

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

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

------
gallexme
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)

~~~
mytailorisrich
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.

~~~
alkonaut
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.

~~~
teh_klev
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:

[https://www.reddit.com/r/policeuk/comments/803y16/drink_driv...](https://www.reddit.com/r/policeuk/comments/803y16/drink_drive_checkpoints_in_the_uk/dustr0o)

~~~
mytailorisrich
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.

~~~
teh_klev
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.

------
kpU8efre7r
>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.

~~~
giarc
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.

~~~
adrr
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.

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

~~~
marcoseliziario
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.

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

------
JoeAltmaier
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.

~~~
blunte
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).

------
kappi
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.

~~~
tasty_freeze
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.

