Researchers Find Breathalyzers To Be Just More Faulty Cop Tech Capable Of Putting Innocent People In Jail

from the may-as-well-just-go-back-to-hunches dept

Good news for motorists: law enforcement is using something just as unreliable as $2 field drug tests to justify arrests and searches. Field drug tests have been known to declare donut crumbs meth and drywall dust cocaine. Yet they're still in use, thanks to their low price point. A costlier apparatus, used to determine blood alcohol levels during sobriety tests, appears to be just as broken as cheap drug tests.

Alcotest, made by German medical tech company Draeger, is used by a large number of US law enforcement agencies. Challenges to test results led to Draeger turning code over to defense attorneys, who soon discovered a lot of variables affected breath tests -- many of which weren't addressed by the device's software or default settings used by officers. Zack Whittaker at ZDNet has the full report:

One attorney, who read the report, said they believed the report showed the breathalyzer "tipped the scales" in favor of prosecutors, and against drivers.

One section in the report raised issue with a lack of adjustment of a person's breath temperature.

Breath temperature can fluctuate throughout the day, but, according to the report, can also wildly change the results of an alcohol breath test. Without correction, a single digit over a normal breath temperature of 34 degrees centigrade can inflate the results by six percent -- enough to push a person over the limit.

The quadratic formula set by the Washington State Patrol should correct the breath temperature to prevent false results. The quadratic formula corrects warmer breath downward, said the report, but the code doesn't explain how the corrections are made. The corrections "may be insufficient" if the formula is faulty, the report added.

The Washington State Patrol, whose device/software was being examined in this case, said it did not install the breath temp component. That eliminates one questionable variable in this case. Other law enforcement agencies may have installed the component without realizing it could result in false positives. But it's far from the only variable affecting test results the examination of Draeger's software uncovered. The Washington State Patrol also disabled another feature that might have prevented false positives.

The code is also meant to check to ensure the device is operating within a certain temperature range set by Draeger, because the device can produce incorrect results if it's too hot or too cold.

But the report said a check meant to measure the ambient temperature was disabled in the state configuration.

"The unit could record a result even when outside of its operational requirements," said the report. If the breathalyzer was too warm, the printed-out results would give no indication the test might be invalid, the report said.

The State Patrol was more equivocal in its repudiation of this finding. It said it had been "tested and validated in various ambient temperatures." Draeger itself insisted the unit will not produce readings if the device is operating outside of recommended temperature ranges.

The report also noted there appeared to no steps taken to counteract normal wear-and-tear. The fuel cell used to measure alcohol levels decays over time -- a time period accelerated by frequent use (sobriety checkpoints, for instance). This can also affect test results if the decay isn't factored in. Draeger says its devices should be re-calibrated every year. The Washington State Patrol only require one recalibration six months into the device's lifespan.

Challenges against the device's test results have occurred in other states. Massachusetts -- a state where substance abuse-related evidence has never been more unreliable -- hosted one legal battle over the devices' reliability. A ruling in 2014 declared test results obtained over the previous two years "presumptively unreliable" after it was discovered that only two of the state's 392 breathalyzers had ever been properly calibrated.

This battle between critics of the devices and their deployment methods (untested, uncalibrated) and a judicial system that still insists the devices are reliable enough has gone on for most of a decade. Added to the mix is Draeger's own legal action. This preliminary report, distributed to defense lawyers at conference last year, was the subject of a cease-and-desist letter from Draeger, which claimed the report violated a protective order it had obtained from a US court, prohibiting the distribution of its source code. But no source code was distributed and the C&D appears to Draeger attempting to prevent questions about its device's reliability from spreading further than a handful of court cases. And in those legal challenges, Draeger has been able to keep discussion of its devices and software under wraps via injunctions.

While the report's authors claim the report is still in its preliminary stages and should not be considered the final word on breathalyzer reliability, this initial examination doesn't suggest deeper digging will find a more reliable machine underneath the surface-layer flaws.


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  • This comment has been flagged by the community. Click here to show it
    identicon
    Anonymous Coward, 14 May 2018 @ 9:39am

    Advocating that alcoholics be let behind wheel to endanger all.

    "inflate the results by six percent -- enough to push a person over the limit." -- Close enough. -- Oh, he wasn't "DRUNK" when crashed into you isn't any solace.


    Now, censor this as usual, kids, because it's on-topic reasonable argument which Techdirt can't stand to even let be seen.

    reply to this | link to this | view in chronology ]

    • icon
      Dan (profile), 14 May 2018 @ 9:52am

      Re: Advocating that alcoholics be let behind wheel to endanger all.

      Apparently "on-topic reasonable argument" means "grossly misrepresenting the point of the article in order to set up a straw man." If the laws on DUI are going to be tied to a specific blood alcohol content (as they are), then the devices used to ascertain that blood alcohol content (and therefore send people to jail) need to be verifiably accurate. That, and only that, is the point of the article.

      reply to this | link to this | view in chronology ]

    • identicon
      Anonymous Coward, 14 May 2018 @ 9:59am

      Re: Advocating that alcoholics be let behind wheel to endanger all.

      If the driver is inebriated enough to be dangerous, there should be other signs beyond just failing an unreliable test. (Besides, there are plenty of very dangerous sober drivers, so arresting only the ones that fail a breathalyzer is the wrong approach anyway.)

      Nothing contemplated here says the cops will stop using it. Rather, it is at best an indication that the accused can more readily beat the charge when it is filed - not that it will get them out of the initial arrest. Cops enjoy enough immunity that they could likely get away with arresting the driver on a claim that "I smelled alcohol on him/her", "He/she looked impaired", etc. Courts love to defer to cops on issues like this, and since courts routinely find that being arrested was "not a big inconvenience", the cops have no reason not to push their luck when they have the socially popular idea of "protecting the public from drunk drivers" as their cover.

      reply to this | link to this | view in chronology ]

    • icon
      McCrea (profile), 14 May 2018 @ 10:05am

      Re: Advocating that alcoholics be let behind wheel to endanger all.

      And we should prosecute everyone who does 50mph in a 55 zone a speeding ticket be "Oh, he wasn't "SPEEDING" when crashed into you isn't any solace."

      Personally, I find you far more than 6% short of being reasonable. Only 6% over the fine line of sanity. Only 6% short of a full deck? Only 6% dimmer than a burnt out bulb?

      Geez, first time in two years I've logged into to make a comment. I guess I only respond to 6% of the trolls.

      reply to this | link to this | view in chronology ]

      • identicon
        Thad, 14 May 2018 @ 1:09pm

        Re: tl;dr

        Geez, first time in two years I've logged into to make a comment.

        Oh God, now he's going to spend ten posts ranting about how you're a zombie.

        reply to this | link to this | view in chronology ]

      • icon
        TripMN (profile), 14 May 2018 @ 7:28pm

        Re: Re: Advocating that alcoholics be let behind wheel to endanger all.

        Welcome to Club Zombie(tm)

        The fact you took the time to sign in will just make the tin hats spin on their heads.

        reply to this | link to this | view in chronology ]

    • identicon
      Anonymous Coward, 14 May 2018 @ 10:16am

      Re: Advocating that alcoholics be let behind wheel to endanger all.

      Advocating for laws being changed to "close enough" is not a "reasonable argument."

      reply to this | link to this | view in chronology ]

    • identicon
      I.T. Guy, 14 May 2018 @ 10:24am

      Re: Advocating that alcoholics be let behind wheel to endanger all.

      "because it's on-topic reasonable argument"

      The former, yes; The latter, no.

      As usual.

      reply to this | link to this | view in chronology ]

    • identicon
      Anonymous Coward, 14 May 2018 @ 10:59am

      alcoholics to be let behind wheel to endanger all.

      is actually what you advocate by actively ignoring obvious flaws of the device.

      I know at least one jurisdiction, where breathalyzer test is only advisory, leading - in case of probable DUI - to a full blood work-up. Why take a risk of a drunks returning behind the wheel after a botched test, if you can do it properly?

      reply to this | link to this | view in chronology ]

    • identicon
      Anonymous Coward, 14 May 2018 @ 8:26pm

      Re:

      IP addresses, drug tests that don't work, breathalyzers with horrible calibration...

      You have a very vested interest in defending dodgy tech instead of, you know, actually improving on the damn things to reduce false positives, don't you blue? Hitting a little too close to home, aren't we? After all, that's what the RIAA is deservedly known for. Having the accuracy of a blind gunman wielding a shotgun, trying to shoot the far side of a barn while facing the opposite direction!

      reply to this | link to this | view in chronology ]

  • identicon
    Anonymous Coward, 14 May 2018 @ 9:44am

    Sounds like a get out of DUI free card to me

    For defense attorneys, this device and its known unreliability mean that any police department using it will find itself on the losing end of court cases.

    reply to this | link to this | view in chronology ]

    • identicon
      mcinsand, 14 May 2018 @ 9:52am

      Re: Sounds like a get out of DUI free card to me

      Exactly! Documented unreliability will kneecap our prosecutors unless we throw the integrity of our enforcement system into the toilet. We need to find the problems, define and documents performance limits, and ensure equipment maintenance. Otherwise, our highways will become even more dangerous.

      reply to this | link to this | view in chronology ]

      • identicon
        Anonymous Coward, 14 May 2018 @ 1:20pm

        Re: Re: Sounds like a get out of DUI free card to me

        "the integrity of our enforcement system"

        Like such a thing has ever existed.

        reply to this | link to this | view in chronology ]

    • icon
      OA (profile), 14 May 2018 @ 9:57am

      Re: Sounds like a get out of DUI free card to me

      Not really. Powerful defendants with high priced lawyers will get these tests tossed easily. The poor(er), not so much.

      reply to this | link to this | view in chronology ]

      • identicon
        Anonymous Coward, 14 May 2018 @ 1:22pm

        Re: Re: Sounds like a get out of DUI free card to me

        Poor will be forced into a plea "bargain" thus adding to the private prison bottom line - it's all good for the fat cat assholes.

        reply to this | link to this | view in chronology ]

  • identicon
    Anonymous Coward, 14 May 2018 @ 10:20am

    Not a "full" report

    Zack Whittaker at ZDNet has the full report

    Had the report: "A person with a copy of the report allowed ZDNet to read it." Just a preliminary version: "Their research was left unfinished, and a final report was never completed." And no version is being made available to the readers.

    reply to this | link to this | view in chronology ]

  • identicon
    Anonymous Coward, 14 May 2018 @ 10:46am

    I don't know the actual procedures in place here, but originally the the field breath test was meant to screen for the need for an *accurate* blood test done at the station. It was never meant to be more than that, and never meant to be the sole evidence at trial.

    That's the original explanation, anyway. Obviously that's no longer the case in many (most? all?) states. Between budget cuts and lazy procedures and over zealous police and prosecutors trying to appear "tough on crime" questionable evidence is constantly being brought to trial while the jury is never told there's no, little, or how much actual evidence is scientifically proven or even what the real incidence of a particular piece of evidence (like a partial finger print) would "hit" on 1 in X number of people. Also, did you know you can be legally removed from a jury for mentioning jury nullification despite it being an important part of our judicial system?

    I have encountered one jury hanging on breathalyzer evidence though. Back in Florida about 15 years ago. Vicarious, it was my daughter-in-law on the jury. One of the jury members refused to convict because, apparently, the ONLY evidence presented was a field breathalyzer test. The juror already knew that the breathalyzers could give false results if someone had an oral piercing, which this defendant did. Back then the mfg of these devices was refusing to show the source code and procedures for calibration, and this was becoming a big bone of contention that was beginning to cause problems as the information became more widely known how inaccurate these devices can be. I don't know if the prosecution retried the case later, I never heard. They likely did if they polled the jury and found it was only one hold out.

    reply to this | link to this | view in chronology ]

    • identicon
      Anonymous Coward, 14 May 2018 @ 11:45am

      Re:

      "Jury nullification" is "an important part of our judicial system"

      No, it is a consequence of our judicial system, and not an intentional feature. A powerful and useful one.

      Mentioning Jury nullification suggests to the court that you are going to go weigh questions of law, not questions of fact, which leads to dismissal. In fact, mentioning during the selection process suggests that you may be prejudiced about the laws in play, and you would then be dismissed by the prosecution for cause. Beyond that, Jury nullification, when sought by a member of the jury, can extend the deliberation, placing further burden on the courts, worsening issues of court costs, overcrowded dockets, and the cost of a vigorous defense.

      It leads to more pressure being used to prevent jury nullification from being a thing, to move towards plea bargains instead of trials. And breathalyzer evidence is great for that pressure. All you need is the arrest, and the threat of waiting a few days in jail before they either charge you or let you go.

      You don't know the procedure? Here is the procedure. Get a false positive on the breathalyzer. Arrest them, and sit on them. Simple, easy, and Jury Nullification cant do shit for it.

      In the end, that doesn't matter. An unreliable breath test is not probable cause for arrest or a blood draw, your blood being considered the height of personal information. And yet, it is. Its not about the convictions, its about the arrests.

      reply to this | link to this | view in chronology ]

      • icon
        Stephen T. Stone (profile), 14 May 2018 @ 3:31pm

        Re: Re:

        If I believe a law is unjust, I will not vote to convict someone of breaking that law. If that makes me a bastard, I will carry that label with pride.

        reply to this | link to this | view in chronology ]

        • identicon
          Thad, 14 May 2018 @ 4:50pm

          Re: Re: Re:

          Jury nullification is a complex topic. It can be a valuable tool for civil disobedience, or it can be used by a jury of bastards to let the guilty go free. The trial of Emmett Till's murderers is probably the most famous example of the latter.

          reply to this | link to this | view in chronology ]

  • identicon
    Anonymous Coward, 15 May 2018 @ 8:48am

    Who cares? Self driving cars will eliminate drunk driving anyway. Give it 20 years and won't be an issue. Until then, suck it up.

    reply to this | link to this | view in chronology ]


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