MN Supreme Court Backs Reasoned Requests For Breathalyzer Source Code

viralMeme writes with news that the Minnesota Supreme Court has upheld the right of drunk-driving defendants to request the source code for the breathalyzer machines used as evidence against them, but only when the defendant provides sufficient arguments to suggest that a review of the code may have an impact on the case. In short: no fishing expeditions. The ruling involves two such requests (PDF), one of which we've been covering for some time. In that case, the defendant, Dale Underdahl simply argued that to challenge the validity of the charges, he had to "go after the testing method itself." The Supreme Court says this was not sufficient. Meanwhile, the other defendant, Timothy Brunner, "submitted a memorandum and nine exhibits to support his request for the source code," which included testimony from a computer science professor about the usefulness of source code in finding voting machine defects, and a report about a similar case in New Jersey where defects were found in the breathalyzer's source code. This was enough for the Supreme Court to acknowledge that an examination of the code could "relate to Brunner's guilt or innocence."

Comments

Hm.

[Bruce Perens]

Does this mean that if a defendant presents a copy of Bruner's exhibits, he's likely to get the go-ahead in that state?

Re:Hm.

[spun]

That is mentioned as a consequence of the ruling. Now it remains to be seen whether the manufacturer will release the source code. If they won't, presenting a copy of Bruner's exhibits will be a 'get out of jail free' card for drunk driving in Minnesota. Which will mean the state will have to go with a manufacturer that WILL provide the source. Nice.

Re:Hm.

[Bruce Perens]

It means that all states will have to raise standards for the embedded code in those things. Embedded code often really stinks.

Re:Hm.

[spun]

Wait, wait, wait. You're saying embedded code often stinks? Don't we use embedded code in voting machines? My God, has anyone checked them? This sounds like it could be a real problem, I think we need to notify the authorities.

Re:Hm.

[profplump]

Or they could go with a detection method that's actually accurate and verifiable, rather than one that makes a whole slew of assumptions about your body and leaves no sample for third-party testing. If we're supposed to be measuring BAC, couldn't we just sample your blood?

But that's contrary to the prohibitionist agenda that defines "drunk" using arbitrarily low readings from a breathalyzer, so it's unlikely to occur.

Re:Hm.

[Mr. Freeman]

Here in Colorado the breathalizer is optional. Of course, refusal to take the test means they can haul you off to jail.
Once they take you to whatever office you can take either:
A) Blood test
B) Brethalater (desk-top version of a breathalizer, presumably more accurate)

If you refuse to take A or B then your license is revoked for a year.

Re:Hm.

[Zero__Kelvin]

"Mod parent up. His post is 100% correct. In the United States if you refuse a Breathalyzer you will be administered a blood test (not that this can take several hours in which you may or may not sober up...)." [Emphasis Added}

This is not a federal issue, and the procedures vary from state to state. In Pennsylvania you have to submit blood even if you take a breathalyzer and plead guilty or they take your license for a year. In Massachusetts you can take a breathalyzer or a blood test, but can only do the latter if you can afford to pay a personal physician to show up at the station and perform the test. (Read: Aren't poor and/or ignorant)

So you see, different states abuse citizens right in different ways ;-)

Re:Hm.

[d'fim]

Correction:
You have to refuse the breathalyzer and the blood test for the penalty to kick in.

Re:Hm.

[Arthur Grumbine]

... I think we need to notify the authorities.

I dunno, maybe we should vote on that.

Re:Hm.

[bbhack]

In Massachusetts you can take a breathalyzer or a blood test, but can only do the latter if you can afford to pay a personal physician to show up at the station and perform the test. (Read: Aren't poor and/or ignorant)

It's good to know that Massachusetts hates the poor and ignorant. I was unclear on that. Any state that hates poor and ignorant can't be all bad.

Fishing expeditions

[Brian Gordon]

So essentially challenging evidence gathering methods is insufficient, but making colorful posters and waving around a PhD is fine?

Re:Fishing expeditions

[Bruce Perens]

At times I have been an expert witness. I look at the evidence, and make a reasoned finding which I explain what I think, in terms a layman can apprehend, to the court reporter. If I can't ethically testify in the customer's favor, I tell them so and end the engagement before there is a chance for me to testify.

My cases rarely have much to do with a judge, because civil cases tend to settle. And then get sealed, so you can't see them.

Re:Fishing expeditions

[houstonbofh]

So essentially challenging evidence gathering methods is insufficient, but making colorful posters and waving around a PhD is fine?

Yes. Like a slashdot legal opinion is worthless, and someone who has passed the bar has value. Who is questioning the procedure is relevant.

Re:Fishing expeditions

[Bruce Perens]

I've never found it very difficult to understand the lawyers and judge's case findings. Yes, they use a little Latin, but you can learn the 100 most used words and look up anything more that comes up on the web. And they cite cases, which you can look up too.

Are you talking about contracts?

Re:Fishing expeditions

[justinlee37]

That's pretty circular logic. How can we speculate as to what might be wrong with it when we can't even see it?

Re:Fishing expeditions

[JustNiz]

I think the problem here is that the guy caught drunk-driving didn't pass the bar. He stopped and went in.

Re:Fishing expeditions

[Trepidity]

I think they're more saying that you need some argument for why you're making the request. The fact that it's sufficient to make colorful posters and wave around a PhD just means that the MN court has put a fairly low bar on how good the argument has to be--- but they do require that you make some sort of argument. The guy whose request was rejected appears not to have made any argument at all for why retrieving the source code would plausibly help his trial; he just stated flatly that it might, which is not usually sufficient. The other guy made some effort to argue why the source code for this sort of device was relevant to his case.

Re:Fishing expeditions

[Jane Q. Public]

Nevertheless, several of our Founding Fathers expressed the opinion that the law should be restricted to (and interpreted as) English as spoken by the common man at that time. Latin terms and legalese were perceived as an enemy to freedom even then.

Re:Fishing expeditions

[ari_j]

Lawyers and judges not only cite sources, but are strongly encouraged to do so very precisely to an extent that other professions never do. This is both as a matter of professionalism and as a matter of getting your point across. It is more credible to read a sentence and see that it is cited to a specific paragraph in each of five different sources, with a relevant quote from two of them in parentheses, than it is to read a sentence and just see an author's name and a year after it. Making your points in a succinct, reasoned, and credible manner is how you win a legal argument. And that's probably why the APA citation format is less precise: If you don't convince someone your psychology term paper is right, nobody loses their money or freedom.

Legal arguments can be difficult to read if you lack the background. For instance, a legal brief about discretionary immunity to a lawsuit might not make much sense if you are not aware of what immunity means in that context or if you don't know that the way to avoid a jury ever hearing a case about an injury is to convince the judge that this mysterious "duty" thing is missing. But, given only a basic background, any properly-written legal memorandum or brief will be easy to read, with short sentences and well-organized paragraphs, not using obscure words.

By contrast, legal agreements are hard to read because the lawyers who write them spend the entire time trying to think of what loophole they might have missed and how to plug it. It borders on irony that their efforts to be absolutely clear in exactly what every term of the agreement means (and thereby preventing other lawyers from saying they mean something else) result in the agreement as a whole being nearly impossible to comprehend in its entirety at any one moment. The sickening part is that a brief is written for a more legally educated audience than a contract, since the person against whom the contract will be enforced is likely not to be an attorney or judge, and if a person can't understand a contract then he has a slightly better chance of getting out of it.

Re:Fishing expeditions

[Dhalka226]

I remember a discussion about this on /. awhile ago, and somebody brought up a point I couldn't quite remember. I hopped over to the wikipedia page to look for something about found this:

"Some breath analysis machines assume a hematocrit (cell volume of blood) of 47%. However, hematocrit values range from 42 to 52% in men and from 37 to 47% in women. A person with a lower hematocrit will have a falsely high BAC reading."

and this:

"Breathalyzers assume that the subject being tested has a 2100-to-1 'partition ratio' in converting alcohol measured in the breath to estimates of alcohol in the blood [. . .] However, this assumed 'partition ratio' varies from 1300:1 to 3100:1 or wider among individuals and within a given individual over time."

I'm not sure what, exactly, I was remembering from the previous discussion; these may or may not be it. What I do remember is that it was essentially that, somewhere in this code, there are assumptions made and that the validity of the assumptions is going to directly affect the validity of the code.

Without knowing what, exactly, this machine is measuring and what it is assuming about the individual taking the test, it's impossible to know whether or not there's any reason to believe the test was inaccurate. Since both of these people argued this case to the Minnesota Supreme Court, I hope they both feel they're innocent.

I suppose this guy's lawyer should have made that argument. On the other hand, I don't think it's unreasonable for judges who are going to oversea DUI cases to understand that a breathalyzer is not, by any stretch, conclusive evidence. Use it to haul somebody in, by all means -- then get yourself a blood test. Bill the person being charged for the test for all I care. The breathalyzer itself should not be admissible in court. (I'm ignoring, by the way, the fact that something like having taken cough medicine could also affect the results.)

Re:These guys are no heroes

[houstonbofh]

I'd hate to see Slashdot supporting these wreckless drunks just because they claim to be l33t haX0rs.

That is the point. If the machine is faulty, they are not "drunks." Kinda like that printer wasn't really seeding Smells Like Teen Spirit. Only by examining the procedure for determining that state, can we know.

That's how science works

[mister_playboy]

I assume breathalyzer evidence is given such great weight because it is "scientific evidence"? Then why shouldn't be subject to peer review... which is a central tenet of science? Without that, it's nothing more than a magical "black box, of unknown accuracy, and does not deserve to be considered "scientific proof"... throw away part of the valid process of science, and you debase the source of its supposed objectivity.

Re:That's how science works

[denttford]

What you seem to miss this is the application of science in law, not science. As a result, the commonly held method of scientific consensus or peer review is not the issue, but rather how American law deals with scientific evidence (and consensus/peer review): Daubert Standard Frye Standard Agree or disagree, there is plenty of literature on the subject; it's not like no one has thought about this.

Re:That's how science works

[sakdoctor]

I'd go a step further, and refuse any breathalyser that doesn't run linux.

Re:That's how science works

[profplump]

It's of know accuracy, and the accuracy is poor, so no one using it wants to talk about it. Even assuming the device functions exactly as designed it's not very good at determining your BAC because it can only measure the absolute count of methyl-group molecules in the sample chamber, not the amount of alcohol in your blood, or even the sort of things you'd need to make a reasonable estimate given the amount of alcohol in your exhaled breath (subject weight would be a good place to start).

Re:That's how science works

[Bruce Perens]

I think you are allowed to refuse a breathalizer in some jurisdictions. If you do, they take you to get a blood draw immediately, and charge you based on the amount of alcohol measured in your blood. I don't know how they measure it.

Re:That's how science works

[ari_j]

In my state, and likely in many others, we have an "implied consent" law. What it says is that you implicitly consent, by signing your name to your driving license, to a breath alcohol test whenever you are stopped for a traffic violation. It also says that, if you revoke your implied consent by refusing a breath test, you automatically lose your license as an administrative matter between you and the department of transportation. Even if you are acquitted of the DUI, you have to take the DOT to court to get your license back, because you broke your agreement in getting it.

We also, as I've mentioned elsewhere in this thread, don't convict you of DUI based on a breath test. The breath test (an SD-2 Breathalyzer machine in most cases) just gives enough evidence to take you in and do a blood draw. This avoids the source code problem, among others, by using well-known, old-fashioned, and I believe published lab methods to measure your blood alcohol content.

Of course, the SD-2 can be used to convict you of being a minor in consumption of alcohol, which makes sense because, whereas the DUI law punishes 0.08% or higher and an inaccurate measurement by the SD-2 can make or break the case, an MIC punishes anything greater than 0%, so an inaccurate measurement only matters if it finds alcohol where there is none, which is vastly less probable than inaccurately measuring the amount of alcohol where there is some.

Re:That's how science works

[Anonymous Coward]

it can only measure the absolute count of methyl-group molecules in the sample chamber

Well, it's alcohol molecules, not methyl groups (I presume you're not a chemist), but yes, that's true.

not the amount of alcohol in your blood, or even the sort of things you'd need to make a reasonable estimate given the amount of alcohol in your exhaled breath

The exhaled alcohol comes from the blood vessels in your lungs. The amount of alcohol in your exhaled breath strongly correlates to the alcohol concentration in your blood, with only very small variations with body size & lung capacity.

(subject weight would be a good place to start).

Subject weight is irrelevant to BAC. You might argue BAC isn't a good measure of impairment, but that's a different story.

Some breathalyzer models may have glitches & errors (which is the subject of this article), but the idea of using exhaled alcohol content to calculate BAC has been proven to be very accurate and has been tested to death.

Re:That's how science works

[sjames]

Daubert superseded Frye and does specifically require that the technique be subject to peer review AND PUBLICATION. That means that the super secret proprietary code in the brethalyser disqualifies it (or should disqualify it) as scientific evidence.

As far as 'generally accepted' goes, since this is essentially a medical test, I would have to presume the medical community's opinion would be relevant. As far as I know, when a doctor wants to know a patient's BAC, they do a blood test every time. Evidently the medical community doesn't consider a breath test to be adequate for determining BAC.

Re:That's how science works

[sjames]

Of course, the SD-2 can be used to convict you of being a minor in consumption of alcohol, which makes sense because, whereas the DUI law punishes 0.08% or higher and an inaccurate measurement by the SD-2 can make or break the case, an MIC punishes anything greater than 0%, so an inaccurate measurement only matters if it finds alcohol where there is none, which is vastly less probable than inaccurately measuring the amount of alcohol where there is some.

Actually, it can be a problem. Many mouth washes contain alcohol (in that case, the breathalyzer is technically correct, but the assumption that alcohol on your breath means you consumed an alcoholic beverage is faulty). Many breathalyzers cannot distinguish ketones from alcohol. Even is the breathalyzer functions perfectly every time, it's not valid to presume guilt based on the slightest trace of a reading.

Re:That's how science works

[Jane Q. Public]

Only in a loose way. And not to the extent currently embodied in law.

There have been MANY studies of this. The reality is not what the lawmakers would have you believe.

First, it is a fact that experienced drinkers can drive safely with a lot more alcohol in their systems than inexperienced drinkers can. (This is one of several ways in which BAC is NOT directly related to driving impairment.) The current legal system does not account for this, and in fact commonly denies it is true, even though the science on this is plentiful, sound, and conclusive.

Some people have a higher physical tolerance for alcohol than others. This is completely separate from the first point. But when you put the two together (some people are more tolerant, and experienced drinkers drive better than inexperienced drinkers do), you end up with a WIDE variety of driving skills, given a certain BAC. This is a fact that the legal system refuses to acknowledge.

Further, the legal limit is set too low. Case in point: the State of Idaho did its own studies, performed through State universities, on driver impairment and BAC. What they found, after rather exhaustive testing, was that at 0.1% BAC, the driving skills of most people were not significantly impaired.

And yet, when MADD put pressure on the legislature to crack down on "driving while intoxicated", Idaho changed the state limit to 0.08%, as was the fad at the time. Even though their own science stated that this would result in the arrest and incarceration of a huge number of people who were not actually intoxicated in any scientific sense of the term.

This was an outright criminal thing to do, and it has indeed led to the arrest, incarceration, and other legal ramifications for countless people who drive, but who are not intoxicated in any realistic sense.

It is any wonder that people -- especially young people -- have lost respect for the law? When some laws become blatantly unreasonable and unjust, the respect for all law goes out the window.

Re:That's how science works

[Buelldozer]

I had a breathalyzer administered roadside by an officer show me as legally intoxicated, which I found very odd since I hadn't consumed ANY alcohol in at least three days.

I absolutely insisted on being taken to the hospital for a proper blood test. The staff there were very much not amused with the officer when my ACTUAL B.A.C. was at .001!

Breathalyzers are great in theory, out in the real world they can AND DO fail.

Re:That's how science works

[sjames]

We bar evidence all the time if it's not reliable. That is particularly true when it might be prejudicial, that is when the judge knows it will LOOK damning to the jury but is in actuality either irrelevant or unreliable. A judge may also instruct the jury to disregard testimony if it fails to meet the relevant standards.A judge may even penalize the prosecution if it knowingly brings a case based only on such inadmissible evidence (though it is more common to simply admonish them and throw the case out). Essentially, refusing to admit evidence is a simple and effective way to avoid adding months to what should be a simple trial and avoid confusing and potentially prejudicing the jury with what will clearly be ruled irrelevant. If that leaves nothing to prosecute, so be it! It's better to let 100 guilty people go than to wrongly convict one innocent.

It could be argued that breathalyzer evidence is hearsay. That is, the breathalyzer is acting as a proxy for it's programmers and designers who claim that it's in-built methodology is valid. That is, the officer is really testifying that "Intoxilizer 5000EN told me that CMI told it that the defendant was intoxicated".

The adversarial process is supposed to be the next line of defense when that is not done. "I think I saw him at..." will be torn apart in court. If we are really appropriately observing the standard of proof and placing the burden of proof on the prosecution, all the defense should need to do is ask "can you demonstrate that that particular breathalyser on that particular night was 100% accurate under those particular conditions? Can you prove that no other medical condition, even a transient one could cause those readings?

In the case of a blood test, the prosecution certainly can prove all of those things beyond reasonable doubt. The methodology is well known, widely peer reviewed and generally accepted as accurate by the medical community. If they have properly retained the sampled blood, the defense can even have a second lab re-test the sample. The blood test is NOT hearsay because the lab submits an affidavit containing their findings and methodology. Because of that, the defense won't likely want to bring it up since it would only serve to further convince the jury of the prosecution's case.

With the breathalyser, the police honestly have no idea how the machine should work and even less idea if it actually does work that way. They can't testify to the methodology of the measurement or adequate controls because that's proprietary information. They can't testify that the machine actually does practice that methodology correctly because the source code is not available for their examination. The sample can't be re-tested by an independant lab because none is retained (nor is it practical to retain one).

Because of all of that, a breathalyser test is an adequate screening test only. If it says you're not under the influence, it's not likely worthwhile to get the blood test. It COULD be wrong about that, but if the officer sees no other evidence that you're impaired, it's close enough. It can help when an officer is genuinely trying to decide if the suspect is intoxicated or if they really are "just tired" or "not feeling well".

Like any screening test, a positive reading only indicates that it is worthwhile to perform the definitive test. Never anything more than that. That is, the screening test IS good enough to establish probable cause for the more invasive test.

Notably, if the police had correctly used the breathalyzer only as a screening test and then performed the definitive blood test, none of this would be before the court today since the breathalyzer would only need to meet the standards for probable cause and the actual conviction would be based on the much stronger evidence of the blood test.

Re:These guys are no heroes

[mccalli]

Wouldn't YOU be pissed if you knew you weren't drunk

Paging Rene Descarte - Monsieur, we need you urgently....

Cheers,
Ian

Re:These guys are no heroes

[maxume]

GP likely speaks American English.

Re:These guys are no heroes

[DarkOx]

I'd hate to see slashdoters ignoring the basic principles of our justice system just to pursue some prejudice against accused drunk drivers.

Like it or not the foundation of out criminal justice system is based on the idea its better to let the guilty go free then the innocent be punished. It might be "PC" to "get tough on drunk driving," but this is a nation of laws or at least it used to be. The burden of evidence is supposed to be on the state. If the state is using equipment that must have its inner workings concealed as evidence. I think in the name of justice we must assume that without other pretty damning evidence its not sufficient to prove beyond a reasonable doubt guilt.

If you can't show me how it works or show that it does work in a double blind test with a sufficient sample size, it would not be a good enough argument for me serving on a jury to convict.

The state is much more powerful than and individual the burden of proof is supposed to be on them. A few numbers on an LED display connected to some box you blow in does not cut it, unless you can tell me a lot about what those numbers mean, how they are determined, if its accurate.

My father wrote the first Felony DWI laws in MN

[cenc]

Thought I would share this, and before a bunch of you start posting BS about the claim of who wrote what, that is not the point. The point is the evolution of MN DWI law and technology.

My father as a prosecutor in Minneapolis in the 60's and 70's started prosecuting drunk drivers for things like felony manslaughter and such. At the time it was just misdemeanor, and often the police would just give someone a ride home. The State legislators and several lobby groups caught wind of it and asked him to write the laws. Those became the first felony laws for DWI in MN, and later where used as a model for other States around the country. Obviously they have been super modified since then, but the fundamental principle that DWI is something serious is still there.

My father went on in private practice as defense attorney in the 80's. Almost all of his acquittals on DWI came down to discrediting the probable cause (i.e. the officer) for the arrest in the first place. Typically the officer's judgment was always front and center (e.g. did he really see him cross the center line on an ice covered road). It got progressively harder as they started adding video cameras and other technology to get someone off on a DWI charge, as the officer's judgment became less important.

I suspect since my father's time, the only thing left to really attack is the validity of the technology itself that measures the crime.

Oh jeez

[GameboyRMH]

Just as one can't prove a negative

Not this crap again...

http://www.google.com/#hl=en&q=can't+prove+a+negative

They can't force a blood draw

[Sycraft-fu]

At least not in any jurisdiction I'm aware of, but you can demand one. This is the way to go too, have them take blood, and demand a sample be taken for your attorney as well. The reason is that the only way to accurately measure blood alcohol content is to, well, measure the amount of alcohol in the blood.

The reason the breathalyzer manufacturers are so scared to have their units inspected isn't because there's something evil in the source, but because they know it is a flawed system. They are things that can be accurate, but only if the assumptions they make are correct, and they aren't for all people. As such you can't guarantee an accurate result. If this gets widely shown in court, well then their devices are likely to lose use with law enforcement.

More or less their method for measuring BAC could be compared to measuring the current running through a circuit by measuring the intensity of the light bulb on that circuit. Such a thing can work and give accurate results, but only if you make correct assumptions. You need to know the efficiency of the bulb, the voltage of the circuit, and if there is resistance anywhere else in there. So if your system was designed for incandescent bulbs but your were measuring a florescent, you'd get the wrong result. Same deal if you were designed for a 120v line and it was a 240v bulb.

This is why the breathalyzer companies have flat out refused to hand over their source in various cases. They know that their market is going to vastly shrink if they do.

So as I said: Always demand a blood sample, and another for your lawyer so it can be independently tested. This, of course, won't do any good if you are actually driving drunk but my advice in that situation is don't. However it will do a good job of keeping you from falsely being charged/convicted.

...And if it floats, it's probably a duck.

[shog9]

I think enough of us who are older have known people to be killed by drunk drivers and I honestly have no idea why drunk drivers are even allowed to live after they kill someone.

So go kill the drunks that killed your friends. Be the vigilante.
Or allow that due process of law should trump personal feelings in these matters.

The bottom line is, if someone is getting pulled over for DUI, its because they were already obviously driving smashed.

People drive poorly for all sorts of reasons apart from intoxication. Being tired, or distracted, or suffering from a condition that causes poor night vision all too frequently lead to accidents.

And not everyone who gets pulled over is guilty of something. Cops make mistakes too...

Re:If it looks like a drunk, it probably is.

[houstonbofh]

>

The bottom line is, if someone is getting pulled over for DUI, its because they were already obviously driving smashed. You can see them when you drive - weaving, going slow, forgot to put the headlights on, maybe stopping too soon or too often... and for what? Really, for what do people do this?

I hope you are never the cop who pulls someone over in diabetic keto acidosis... Looks like a drunk, smells like a drunk, acts like a drunk... And if you just dump them in the drunk tank, they will die and you will be on trial.