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DUI Defendant Wins Source Code to Breathalyzer

MyrddinBach writes "CNet's Police Blotter column looks into a Minnesota drunk driving defendant case with a twist. The defendant says he needs the source code to the Intoxilyzer 5000EN to fight the charges in court. Apparently the company has agreed to turn over the code to the defense. 'A judge granted the defendant's request, but Michael Campion, Minnesota's commissioner in charge of public safety, opposed it. Minnesota quickly asked an appeals court to intervene, which it declined to do. Then the state appealed a second time. What became central to the dispute was whether the source code was owned by the state or CMI, the maker of the Intoxilyzer.'"

10 of 638 comments (clear)

  1. Additional info by y2imm · · Score: 3, Informative

    "Wetzel was arrested at his home on Feb. 25 after allegedly rear-ending a car with his pickup truck and then driving off. He faces five gross misdemeanor charges, including causing bodily harm and driving while intoxicated." FREDERICK MELO Pioneer Press

  2. I bet the reason there was resistance.. by Sloppy · · Score: 4, Informative

    ..has nothing to do with this case, and little to do with who holds the copyright. What if he does find flaws, and others have already been convicted using output from the same machine? Suddenly, all those past cases come back up.

    I guess the lesson here is: the source should already have been public and heavily scrutinized. I don't want my government spending my tax money and wasting time in court, to get convictions based on evidence from mysterious unaudited machines. Why? Because sooner or later, some defendant is going to want the mystery peeled back. Some defendant is eventually going to want a fair trial. Might as well give that fair trial to the first one, so that a bunch of expensive shit doesn't have to get re-done (or so that a bunch of guilty people don't end up walking free, simply because the cops used a defective machine that ended up collecting untrustworthy "evidence").

    Keep mysteries out of court, from the start. Don't let a big list of convictions that depend on them, build up. The chances of the device being defective are probably pretty low, but you know there's gotta be some prosecutors with pits in their stomachs.

    --
    As copyright owner of this comment, I authorize everyone to defeat any technological measure which limits access to it.
  3. History of these machines in Minnesota by scanlanj · · Score: 3, Informative

    The previous machine, the Breathalyzer, went out of use when it was proven (by defense attorneys) that it was susceptible to RFI. The "new" machine, the Intoxilyzer5000 (and this was 25 years ago) was microprocessor based. It had an RFI detection circuit which was supposed to invalidate results if RFI was present. Other known issues are burping and chewing tobacco. Trouble is, the RFI detector was a comparator driving a login input. Without the software, you can't prove the box's performance from a white box perspective. That's trouble when you're relying on a machine vs. videotaped evidence of impairment.

  4. Yes, it probably does... by neapolitan · · Score: 4, Informative

    A low-carb diet (e.g. Atkins diet) can indeed make you "ketotic" and raise your breath acetone level.

    From your college chemistry course acetone has a C=O bond, while alcohol is a C-OH bond.

    Cheap breathalyzers will use a chemical reaction to detect the alcohol in your breath -- often potassium dichromate (these are the ones that go from red to green with alcohol).

    More advanced models (such as the ones the police would use, would use essentially spectroscopy to try to measure the resonant absorbance of the C-OH bond. This would not be fooled by acetone, which has a much different absorbance of the C=O (approximately 1700 cm-1 IIRC). There are also variants of this method.

    If you are ever innocent and accused, get a blood test, which really is a quantitative direct measurement and can be confirmed, with very little chance of being fooled.

    If you are not innocent, **IN THEORY** the easiest way to lower your reading is to silently hyperventilate prior to blowing. This would prevent equilibration of the alcohol in your bloodstream with the air in your lungs that you just breathed in and out. It is far from perfect, and I would strongly advise to never drive drunk, nor rely on this method.

    Additional references: http://wiki.answers.com/Q/Could_elevated_ketone_le vels_produce_inaccurate_Breathalyzer_results

    --
    Slashdotter, ID #101. UIDs are in binary, right?
    1. Re:Yes, it probably does... by neapolitan · · Score: 3, Informative

      Yep -- we have a varied audience on Slashdot though, so it is necessary to simplify things a bit. When reading esoterics on kernel hacking, I appreciate a simplified overview. You can't be an expert in every subject.

      I was a chemistry major; I have seen an OH peak, and know the range, and am intimately familiar with spectroscopy... The points you raise are well taken -- yes, the local environment would depend somewhat. However, when running a typical IR spec, how much do these things affect the absorbance? Would a typical IR spec vary with lab conditions / if your AC is on/off, or if the room was hot or cold? The human body would actually provide quite a controlled environment (36 to 38 degrees, high humidity) for measurement. Thus ambient temperature would be relatively constant, provided the person can breathe at a consistent rate. I don't think this would affect readings much, and would be very easy to empirically determine.

      Acetone itself would not affect it much on the levels that a ketotic person could produce. Again, I said *much*, not theoretically or at all. I think your estimates (one -> six beers) are way off.

      The proof is in the data -- none of us can say that the presence of acetone would do this without trying it, and I acknowledge the improbable possibility.

      Do you want to see for yourself -- look at the relative contribution to the spectrum:

      http://www.bluffton.edu/~bergerd/classes/CEM222/In frared/oxygen.html

      That is why if you are truly innocent, demand a (unfortunately invasive) blood test and put the issue to rest.

      --
      Slashdotter, ID #101. UIDs are in binary, right?
  5. Just don't open your mouth by nate+nice · · Score: 3, Informative

    We're already seeing a ton of people with absolutely no legal background commenting on legal things. Here's a tip: the law doesn't work like you probably think it does. The law is rational or reasonable. It's a jumbled mess of subjective orders and expressions that lawyers can mold into defense or complaint.

    Looking at the source code could very well be the basis for a very solid defense that beats whatever state statues and ordinances the defendant is suspected of violating. We have no idea what's in the code so why not? Crappy programmers probably wrote the software and it probably wouldn't be hard to find something that doesn't function right or doesn't map just right to a state issued requirement for the system.

    If this gun reading is the states main piece of leverage it's because this device conforms to some strict requirements defined by the state. So maybe looking at the code will show that it doesn't and that the machine is in fact illegal.

    Lastly, if you ever get pulled over for something like this, don't talk. That is when they ask if you've been drinking, always say no. What does "drinking" mean? Well, it's not up to you to define this at that time. Let your lawyer handle it. Never tell a cop you might be breaking the law. Because once you've admitted that you have been drinking, they can ask you a whole bunch of other questions that can only hurt you. How much? For how long? Where at? Where are you going? With who?

    Here's a sample:

    Officer: Have you been drinking?

    You: No.

    Officer: I smell alcohol.

    You: I haven't been drinking, officer.

    He'll still ask you to get out and do his little tests. But you've never admitted to anything. This can help a lot down the road. In short, never say anything you don't have to.

    --
    "If you are a dreamer, a wisher, a liar, A hope-er, a pray-er, a magic bean buyer ..."
  6. Re:state==public domain? by pyite · · Score: 4, Informative

    America has some problems, but I don' think we're to the point yet where they can arrest you on "suspicion of drunk driving" then use that to "forcibly take a blood sample".

    Yes, that is close to the reality.

    In the case of drunk driving, most states have adopted the law that if you are driving a vehicle, you have then given consent to submit to the approved test to find out if you're driving under the influence of alcohol. When you are stopped and you're not sure of what your alcohol level is, you cannot refuse to take a breathalyzer test. As soon as you got your drivers license, you gave consent in advance to do this. If you refuse, you will find yourself in bigger trouble than you would have by submitting to the test. This implied consent is automatic in the case of anyone who drives a vehicle. From: http://www.lawcore.com/dui-dwi/what-is-implied-con sent.html.

    So, you've agreed to it in advance by having a driver's license. You get to pick your poison in terms of what kind of test it is.

    --

    "Nature doesn't care how smart you are. You can still be wrong." - Richard Feynman

  7. Re:What about by Albanach · · Score: 4, Informative

    Having spent time in North Italy (Lots of mountain roads), I can say that I saw many people out to lunch split a bottle of wine between 2 or 3 people, and drive back to work. In all my time there, I didn't see one wreck. Not one.
    Then you were either lucky or weren't looking for them. Italy has one of the worst accident rates in Western Europe and drink driving is currently a hot political topic following a sixteen year old girl being hit and killed by a driver three times the limit. More here from the Herald Tribune
  8. Re:What about by terrymr · · Score: 3, Informative

    Alcohol related is a world away from alcohol caused - most of those stats refer to accidents where somebody present had had a drink in the last 24 hours.

  9. Re:state==public domain? by Idarubicin · · Score: 5, Informative

    It's the truth. 0.08 is below any significant level of impairment under normal driving conditions....

    First of all, you need to cite some sort of source for a statement like that. (A review by Fell and Voas reports that reducing the legal limit from 0.10 to 0.08 reduced alcohol-related crashes, injuries, and fatalities by between 5% and 16% in the United States; they report further statistically significant reductions in fatalities in jurisdictions that have moved to a limit of 0.05.)

    Second - as other posters have noted - how prepared are you to deal with a surprise abnormal condition?

    Third, nice weasel word--below any 'significant' level of impairment? What does that mean?

    Fourth, I should hope that the limit would be below the level of significant impairment under any condition. There's no compelling reason why anyone should have to drive with any alcohol in their blood; any limit ought sensibly to include a margin of safety.

    --
    ~Idarubicin