# .06 Driving Under The Influence

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## Re: .06 Dui

Quoting cdwjava
Sorry, but if we are talking about the proper application of the SFSTs (as presented by NHTSA), the accuracy rate is up to 91% to determine a BAC of .08+ and 93% to determine .10 and higher.
I always have a problem when these statistics are quoted. They are at best misleading due to someone's misunderstanding of the statistics, at worst they are the government's deliberate attempt to obscure the facts.

The problem with the 0.08+ statistics is that they are based on a data set which is fundamentally flawed and biased. 2/3 of the people from the San Diego validation study (where the 0.08 was validated) were above a 0.10 BAC. To put it in easier terms, without even performing the tests an officer could accurately predict someone being over 0.10 with a 66% accuracy rate.

When you look at the three test battery, it is very good at accurately predicting someone is lower than 0.08 when their BAC is say less than 0.04. They are accurate is predicting someone is higher than 0.08 when someone have a measured BAC of greater than 0.10. But when you look at the target zone BACs, where an officer really needs these tests to be accurate (0.06 - 0.08) the accuracy rate of the tests are between 30% - 60% accurate. A subject is 6 times more likely to be found falsely above 0.08, rather than falsely below 0.08. All based on the San Diego validation study data.

And that is from a peer reviewed article "Statistical Evaluation of Standardized Field Sobriety Tests" by Hlastala et all, published in the Journal of Forensic Science May 2005 Vol 50 No 3.

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## Re: .06 Driving Under The Influence

Quoting afronate
... she passed all the field sobriety tests...
Please remember there is NO criteria for passing FSTs. The official results are either "fail", or "inconclusive".

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## Re: .06 Driving Under The Influence

Quoting LabMonkey
Please remember there is NO criteria for passing FSTs. The official results are either "fail", or "inconclusive".
Not true.

They are evaluated for how many "clues" are observed. These are then used to help the officer form the opinion as to the sobriety of the driver. Typically two clues indicates a failure to pass the test.

- Carl

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## Re: .06 Dui

Quoting LabMonkey
I always have a problem when these statistics are quoted. They are at best misleading due to someone's misunderstanding of the statistics, at worst they are the government's deliberate attempt to obscure the facts.
Take up the facts with NHTSA and with the universities and agencies that conducted the tests. You don't have to believe them, but they are the legal standard all the same.

The problem with the 0.08+ statistics is that they are based on a data set which is fundamentally flawed and biased. 2/3 of the people from the San Diego validation study (where the 0.08 was validated) were above a 0.10 BAC.
Hence the 93% success at determining .10 or higher and "only" 91% at .08. Also note that of the 17,000 or so alcohol related deaths in 2006 some 13,000 were caused by drivers with a BAC of .15 or higher ("only" about 2,000 were between .08 and .15). Most the people we deal with are not in the margins, and are actually quite dangerous.

Since the standard of the law is "probable cause" and not absolute certainty, the standards established and trained are working just fine. The statistics seem to bear out the enforcement is working. If you wish to change the law, go right ahead. However, I doubt that i will be alive long enough sto see a weakening of DUI laws ... I only wish we would see a strengthening of them before I retire - but I doubt even that will happen.

- Carl

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## Re: .06 Driving Under The Influence

Quoting cdwjava
Not true.

They are evaluated for how many "clues" are observed. These are then used to help the officer form the opinion as to the sobriety of the driver. Typically two clues indicates a failure to pass the test.

- Carl
I just re-checked my 2006 criteria, and please excuse me if there is more updated information, but it only talks about if the subject has X or more clues, then someone is likely at or above Y BAC. It does not state any number of clues that is a "pass", nor has there ever been any testing done to show that X clues -1 is Z% likely to be BELOW a given BAC.

It is a common misconception to believe there are passing grades in FSTs, but as a standardized test, the number of clues that someone can obtain and still "pass" must be spelled out and state with what confidence in accuracy of that conclusion.

Technically one doesn't "fail" a FST either, it's either based on X number of documented clues, or the inability to complete the tests, the subject is likely to be at or above a given BAC. There is no proof, or mention of the contra-positive, which is that if someone is under a given number of clues, then they are likely to be under a given BAC.

So the actual results of FSTs are either "above given BAC" or "inconclusive". But most people assume "above given BAC" = "fail".

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## Re: .06 Dui

Quoting cdwjava
Take up the facts with NHTSA and with the universities and agencies that conducted the tests. You don't have to believe them, but they are the legal standard all the same.

Hence the 93% success at determining .10 or higher and "only" 91% at .08. Also note that of the 17,000 or so alcohol related deaths in 2006 some 13,000 were caused by drivers with a BAC of .15 or higher ("only" about 2,000 were between .08 and .15). Most the people we deal with are not in the margins, and are actually quite dangerous.

Since the standard of the law is "probable cause" and not absolute certainty, the standards established and trained are working just fine. The statistics seem to bear out the enforcement is working. If you wish to change the law, go right ahead. However, I doubt that i will be alive long enough sto see a weakening of DUI laws ... I only wish we would see a strengthening of them before I retire - but I doubt even that will happen.

- Carl
I have no problem with FSTs. I think they are an incredibly important tool used by DUI officers in the field. But the quoting of the statistic is grossly improper, as it is based on a fundamentally flawed data set.

Officers should have no problem stating in court that based on my training/experience/obervations/FST results/totality of the situation, I felt there was probably cause to perform a chemical test. But when prosecutor's pull out, or officer's offer up the 91/93 % accuracy rate, it's misleading to the jury.

To say there is a 90% probability someone is above a 0.08 BAC when there is no documentation or proof the FSTs were performed properly (or even at all), and have that information make it to the jury isn't justice. Especially when the truth is, that depending on that individual's actual BAC, the accuracy rate of the FST could be less accurate then flipping a coin.

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## Re: .06 Driving Under The Influence

...and the officers that have hundreds of DUI arrests could do a great job or could get complacent and everyone fails, then relying upon the "breath test" or a voluntary or forced blood draw.

In a few states the officer has the right to pin a person down and stick them without their given consent; they have already consented (implied consent) when they got behind the wheel. Can't wait for the first time they nail a diabetic or even an epileptic on a blood thinner. IMHO, and I studied to be an officer, the only person who should be legally allowed to perform a blood draw is a licensed medical professional in a lab or hospital or a jail hospital. ...but that's just my opinion.

The SFTs aren't the end-all be-all, they help to establish probable cause. ...as if PC wasn't established the first time the perp said something or stepped out of the vehicle.

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## Re: .06 Driving Under The Influence

Quoting LabMonkey
So the actual results of FSTs are either "above given BAC" or "inconclusive". But most people assume "above given BAC" = "fail".
I don't have my instruction manual with me here at home, and I don't have the phrasing in this regard memorized (I probably should as I am an instructor of the SFSTs), but I don't believe that "inconclusive" is in any part of the curriculum. Two or more DIFFERENT clues are given as indicating impairment, or in the common venacular, a "failed" test, but there is no indication of any number indicating greater or lesser impairment by quantity nor is there the term "inconclusive" as it relates to scoring the SFSTs.

- Carl

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## Re: .06 Dui

Quoting LabMonkey
I have no problem with FSTs. I think they are an incredibly important tool used by DUI officers in the field. But the quoting of the statistic is grossly improper, as it is based on a fundamentally flawed data set.
Flawed in your opinion. There are a number of studies that show a great number of things ... I can even find studies that show that incarceration leads to crime, and smoking dope makes you a better driver. The percentages are what they are as a result of the validation studies. The fact that there are other studies that might contradict that doesn't change that fact.

But when prosecutor's pull out, or officer's offer up the 91/93 % accuracy rate, it's misleading to the jury.
Then the defense can challenge that. However, an officer on the stand is probably not going to pull that number out. If he does, it is because he was trained to understand that the validation study determined this figure, not him. if the defense then wants to bring up contrary studies, they may. However, in all my years of DUI and drug enforcement, I have never seen that number challenged as an issue as it just is not relevant. If the tests can be shown to have been conducted properly, and the opinion would seem to have been verified by the FSTs and the officer's observations, then the jury generally goes along with it ... especially since most the FSTs are supported by chemical tests.

The first challenge tends to come based upon probable cause for the stop ... then, the officer's training and ability to properly perform the FSTs ... last, they challenge the machine or testing procedure for the test. Rarely does a DUI that goes to trial actually lose. Most generally plead. And those that DO tend to go to trial often have a perceptible flaw in the case not related to the stats involving the success of the battery.

In 18 years I have NEVER had to use the percentages ... my guess is that the defense understands that my spouting the number is not going to help his case, and I am certainly not qualified to confirm or dispute any contrary studies - nor does it really matter.

To say there is a 90% probability someone is above a 0.08 BAC when there is no documentation or proof the FSTs were performed properly (or even at all), and have that information make it to the jury isn't justice.
This is one reason why many defense attorneys ask the arresting officer to run the tests in the courtroom. It is also why most officers are taught how to conduct and properly document the tests. My officers write them as they conduct them - explaining their instructions in detail and then articulating the response from the defendant.

When they come up with a perfect system, we'll be happy to use it. Until then, this is what we have, it meets the requirements of judicial notice and is accepted in all 50 states as a battery. I like it. Is it perfect? Nope. But, nothing in this world is perfect, and the justice system has never demanded perfection - only reasonableness.

- Carl

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## Re: .06 Dui

Quoting cdwjava
In 18 years I have NEVER had to use the percentages ...
You should try Arizona. Here the percentages are pulled out in every DUI trial (that I've been in, around 40 to date).

Quoting cdwjava
This is one reason why many defense attorneys ask the arresting officer to run the tests in the courtroom.
Demonstrating the FST properly in the courtroom does not equate to the officer performing the test correctly in the field, on the date in question for the defendant in that court case. A paper will be published (soon I hope) that shows the actual percentage of correctly given FST tests is around 50% - 75%, based on video taped FST tests in the field.

Quoting cdwjava
When they come up with a perfect system, we'll be happy to use it. Until then, this is what we have, it meets the requirements of judicial notice and is accepted in all 50 states as a battery. I like it. Is it perfect? Nope. But, nothing in this world is perfect, and the justice system has never demanded perfection - only reasonableness.

- Carl
Agreed. I just object to officers (in Arizona at least), testifying that the battery of SFSTs are 90%+ accurate in determining someone is above a 0.08 BAC, when based on the San Diego validation study, it has been shown the tests can not discriminate that well for "marginal" cases - those same cases that usually end up in court.

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