These Machines Can Put You in Jail. Don't Trust Them. [alcohol breath tests]

[sl8]

From https://www.nytimes.com/2019/11/03/business/drunk-driving-breathalyzer.html

These Machines Can Put You in Jail. Don’t Trust Them.
Alcohol breath tests, a linchpin of the criminal justice system, are often unreliable, a Times investigation found.

By Stacy Cowley and Jessica Silver-Greenberg
Nov. 3, 2019


The Dräger Alcotest 9510 and similar devices from other manufacturers are found in police stations across the country. The test results produced by these machines are increasingly drawing skepticism from judges.Credit...Cooper Neill for The New York Times

A million Americans a year are arrested for drunken driving, and most stops begin the same way: flashing blue lights in the rearview mirror, then a battery of tests that might include standing on one foot or reciting the alphabet.

What matters most, though, happens next. By the side of the road or at the police station, the drivers blow into a miniature science lab that estimates the concentration of alcohol in their blood. If the level is 0.08 or higher, they are all but certain to be convicted of a crime.

But those tests — a bedrock of the criminal justice system — are often unreliable, a New York Times investigation found. The devices, found in virtually every police station in America, generate skewed results with alarming frequency, even though they are marketed as precise to the third decimal place.

Judges in Massachusetts and New Jersey have thrown out more than 30,000 breath tests in the past 12 months alone, largely because of human errors and lax governmental oversight. Across the country, thousands of other tests also have been invalidated in recent years.

[...]

[ck4829]

1. K&R

[olegramps]

14. It seems to me that a person should demand a blood test that goes to an independent lab.

This could be used to challenge breath test accuracy.

[superpatriotman]

2. Just wait for the roadside marijuana tests!

Profits and false feelings of security over people and justice

[Bernardo de La Paz]

5. There is no defined limit for THC because it builds up a tolerance and stays in body fat.

False equivalency leads to false security as you suggest.

It's not like alcohol, where regular users get impaired about the same degree and by about the same quantity as impairs occasional users. It's also partly the case that regular users believe they are less impaired than they actually are.

Regular users will not be impaired 5 hours after toking even though they have levels in their blood much higher than someone impaired with first small smoke in a month.

THC circulates in the blood stream and body fat at detectable levels for up to a month.

The body builds up a tolerance to THC, so regular users consume more to get the same effect.

[Johnny2X2X]

13. They've got a saliva test now

It's not as accurate as needed, but it's getting there and it will simply be a threshold of pass fail for whether a driver has used marijuana in the last several hours. They started to use them in Michigan, but they are not yet accurate enough.

And THC tolerance is much like alcohol tolerance, the user may need more to "feel" the effects, but they will still be impaired at the same rate for driving. Studies have shown that driving with weed in your system has been found to double the chances you'll be the cause of a fatal accident.

[Bernardo de La Paz]

16. The British meta-analysis you refer to is contradicted by much better US DoT NHTSA study

Further, many studies do not remove confounding effects of consumption of alcohol from the equation. There is a significant overlap between those who use alcohol and those who use THC, but the number of alcohol users is much larger, so there is not the same question mark hanging over those studies because it is much easier as a matter of course to eliminate confounding effects of other substances from alcohol studies.

In the largest and most precisely controlled study of its kind carried out by the U.S. Department of Transportation’s National Highway Traffic Safety Administration to research the risks of cannabis and driving,[13] it was found that other "studies that measure the presence of THC in the drivers' blood or oral fluid, rather than relying on self-report tend to have much lower (or no) elevated crash risk estimates. Likewise better controlled studies have found lower (or no) elevated crash risk estimates".[12] The study found that "after adjusting for age, gender, race and alcohol use, drivers who tested positive for marijuana were no more likely to crash than those who had not used any drugs or alcohol prior to driving".[5]

The British study you refer to uses a 3 hour criterion. In places like Canada, 5 hours is the standard.

It is a meta-study, so it probably uses a lot of studies with self-reports (see above excerpt).

A 2012 British Medical Journal meta-analysis indicated that "drivers who consume cannabis within three hours of driving are nearly twice as likely to cause a vehicle collision as those who are not under the influence of drugs or alcohol" and found that acute cannabis use increased the risk of an automobile crash.[14]

[Sherman A1]

3. K&R

Thanks for posting.

[keithbvadu2]

4. Are there any substances that would cause a ridiculously high reading ?

Are there any substances that would cause a ridiculously high reading ?

Yeast?

[Bernardo de La Paz]

18. There are rare cases where person's gut ferments so much alcohol they fail tests

Those people have some disorder with the bacteria in their system. In one case, a man spent time in jail for intoxicated driving. He was actually legally drunk several times over the limit, but verifiably he had not consumed a drop of alcohol long enough ago to not be the cause. He'd been having undiagnosable symptoms for a few months that made him seem like a drunkard.

[WhiskeyGrinder]

6. Gosh, who would have thought.

[Evergreen Emerald]

7. Please. Stop drinking and driving and stop blaming the machine.

The machine is the last of the process.
1. Your driving shows impairment.
2. Your demeanor shows impairment.
3. There is probable cause to arrest for DUI.

And the machines are tested and administered according to specific protocols.

Don't drink and drive.

[USALiberal]

15. Wow, so much wrong there I don't know where to start! Nt

[Bernardo de La Paz]

21. Advice 100%, but otherwise you describe an idealistic fairy tale.

100% don't drink/toke and drive. But as to your other assertions:

1. Impairment probably was (not always of course) reported by a passerby with unknown skills and intentions.

2. The officer SAYS demeanor shows impairment. In idealistic fairy tale worlds there is no racism, sexism, graft or corruption. And no stupidity or lack of training either.

3. The officer SAYS there was probable cause.

4. The machines are not always tested, not always tested properly, and not always administered properly.

5. Training is often insufficient.

6. In this world there are no unicorns.

[Evergreen Emerald]

22. I know a drunk when I see one

and I am not trained. However, one person alleging impairment is insufficient to justify a stop. There must be more.

[DFW]

8. If I were stopped and tested positive for alcohol, I'd shut up and wait for a good lwayer

I don't drink alcohol. Ever. Never have. If I got stopped, it would not be for alcohol (or marijuana) use. If evidence of same were "found" by "law enforcement," I would be in the hands of corrupt cops, and fear illegal confiscation and false arrest. If anyone is familiar with East Texas, they would know that such fears are well-founded.

[Mariana]

17. Indeed.

Some would have us believe that every DUI/DWI/OUI arrest is righteous. It is not so.

[DFW]

20. In some parts of East Texas

The number of DUI/DWI arrests is directly tied to the health of the local economy and the supplemental income requirements of the local constabulary.

[getagrip_already]

9. Some can be intentionally manipulated by police...

There is a type of field unit that has a vent to allow air to escape as you blow into it.

It has been shown that placing a finger over the vent to reduce air flow will increase the reading by more than double.

Cops know all about this. Whether they use it to target certain groups is up to the reader.

Note that I'm not condoning drunk driving, but if the law is going to use an arbitrary measure of guilt or innocence, it should be fairly administered.

[Tarc]

10. People need to read the article before flying off the handle

The science is sound. Cases are being tossed out of court because state agencies are not properly calibrating and maintaining the devices, which can lead to erroneous results.

[Pepsidog]

11. In NJ it was a State Trooper who certifies the machine who falsified documents.

[Jersey Devil]

12. Someone stopped for DUI does not have a choice to trust or not trust the machines

If you don't take the test when requested you lose your license for a period of time for refusing the test, whether or not you are convicted of DUI.

These tests are usually accurate if the machine is properly tested periodically and the officer is trained properly to give the test. As a lawyer I handled DUI cases for many years and a bad machine test was a rarity.

[AlexSFCA]

19. just know that impairment starts at 0.04%

whereas 0.08% is the legal limit. In Cali, blood test is required after the breath test. Phlebotomist will draw blood at the station and the result will be correlated to breath test (time elapsed between the two is accounted for).