Waco Criminal Law Blog : Waco Criminal Lawyer & Attorney : Walter Reaves Law Firm : DWI, DUI, Drug Crimes, Appeals : Waco, McLennan County, Texas

This is my second post on articles from the American Academy of Forensic Sciences Journal. An article that jumped out immediately was "Paradigm Shift for the Alcohol Breath Test" by Michael P. Hlastala. 

Breath testing was developed to determine a person's blood alcohol level. All states define intoxication of terms of the level of alcohol in a person's blood. The best way to test is that is of course to take a  blood sample; however, that takes time; breath testing and easy and quick. Something that can be done by a police officer.

Breath testing is based on the scientific principle that there is an exchange between air and the blood system. You breath in air, which is transferred to your blood system in the lungs. Breath testing is based on the idea that you can estimate a person's blood alcohol content based on the levels in their deep lungs - alveolar air. A mathematical formula is used, which is recognized as being an assumption. The formula is basically an average, which does not apply to everyone.

For any test to be valid, the underlying facts must be valid. According to Dr. Hlastala, the facts supporting breath testing are far from settled. At the beginning of his paper he notes:

In spite of the considerable effort that has gone into the studies attempting to validate the breath test, forensic scientists and toxicologists still have only a basic understanding of the physiological aspects of the the alcohol breath test (ABT) and associated limitations.

The "old paradigm" assumes the amount of alcohol in the breath remains constant as it goes through the lungs. It turns out that is not accurate. In fact, the amount varies - sometimes significantly. The result is that the actual blood alcohol level may be over or under-represented.

The new paradigm recognizes that alcohol is deposited in the airway surfaces during both inspiration and expiration. It also recognizes that the alcohol that comes out in the breath test comes from airway surfaces rather than the alveolar region.

The conclusion reached in the article was:

It is time for forensic scientists to re-examine the ABT to consider the importance of alcohol interaction with the airway tissue during both inspiration and expiration. the result of this interaction is that the breath test is fairer for some subjects than others. Another consequence is that the BrAC continues to increase as the subject continues to exhale. The resulting end-exhaled breath concentration is only partially related to BAC. And, therefore, the ABT exhibits much more variability than previously recognized.

The author recommends decreasing the importance of relying on threshold levels - especially for determining penalties. he also recommends that some margin of error be recognized. Of course, that will never happen, but it something to consider when you have a client that is only slightly over the limit. Based on this research, they may or may not be legally intoxicated.

In Texas, limits are important for not only determining whether someone is guilty or not, but also for determining whether certain conditions are going to be imposed - such as a interlock device. The validity and accuracy of the breath test results is therefore critical.

This article does not break new ground - problems with breath testing have long been recognized. Those problems must be explored - especially in marginal cases. Where someone's future hinges on a machine, the least we can do is make sure the machine is accurate.

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I was going to talk about the ridiculousness about the recent memo from the Texas Forensic Science Commission.  Basically, the memo says they don't have jurisdiction to do anything. They concluded that they do not have "discretion or power to investigate any and every complainant alleging professional negligence or misconduct involving a forensic science." The complaint must involve a "discipline" recognized by the DPS and accredited by DPS. In practical terms, that means they can't investigate the Cameron Todd Willingham case. Yes, I know he promised that would not happen, but anyone who actually believed him deserves what they are getting.

I decided not to talk about that decision, because by now everyone knows what to expect from  the commission. Their goal - at least under the leadership of John Bradley - has been to scuttle the investigation into Willingham, and anything else that might hinder law enforcement.  He has successfully done what many lawyers attempt - avoid doing anything. This new memo goes a long way to ensuring that they will not get involved in anything meaningful.

What struck me about the memo is the power DPS has to both decide what is a forensic discipline, and who gets accredited. DPS is not without its own problems, but despite those problems they apparently have the all knowing ability to determine who should or should not be accredited. It reminds of a story a someone told me about an individual who couldn't  get certified as a fire investigator. He ended up establishing his own organization, and certified himself; that organization now certifies others.

DPS is an arm of law enforcement, and no matter how hard they try they cannot divorce themselves from their identity.  One of the main recommendations of the National Academy of Sciences was that crime labs be separated from law enforcement. If the crime lab should be separate, then surely the authority to accredit such labs should also be separate.

Another thing that struck me, was  the definition of what is a forensic discipline. If it's not a forensic discipline, then no accreditation is necessary. The legislature exempted certain things, and DPS is given authority to exempt others. There are at least two that stand out in the legislature's exemptions - latent fingerprint examination and breath tests. If those two areas don't involve forensic analysis, then what are they? Fingerprint examiners like to talk about how their "scientific" their process is. As for breath tests, the very tests are based on scientific principles. The reason for exempting them probably lies in the fear that they might not be able to overcome the strict scrutiny given to other forensic disciplines.

The commission meets next week, and no doubt will discuss this memo. My guess is that it will be repeat of the last meeting - they will spend all their time talking about what they can and cannot do, and avoid actually doing anything.

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The Texas legislature is in session, which generally means an attack on DWI laws. Every session a number of bills are introduced - most of them bad. Fortunately, few ever make it through the process though.

Texas is one of the few states without legislation authorizing roadblocks. That may change - the Senate yesterday passed a bill that would authorize roadblocks in very limited situations. If you are going to have roadblocks, this bill seems like it contains the appropriate limits. For one, it only applies to the 15 most populous counties, which leaves out many cities - like Waco. It also has a number of restrictions. Checkpoints are limited to 4 hours in lenght, and their existence (although not their location) must be publicized. There are also restrictions on where they can be set up. If you are going to have roadblocks, this appears to be as good as a bill as you are going to get; at least from the standpoint of protecting the ordinary citizen.

Another bill moving along is less circumspect. That bill would authorizie the collection of a breath or blood sample, even where the suspect refuses. Bassically, you can be forced to give evidence against yourself. If this bill passes, I wonder why you would even ask anymore. If you do ask, do you have to tell the person that you are going to get a sample even if they refuse?

With all the economic problems we have, you would think there would be better things to spend time on. This session appears to be no different than most though; crime is still a popular topic. Everyone likes to talk about how tough on crime they are. I'm not sure that is as important to voters as it is politicians, but the perception remains. If nothing else, you don't have to address the really important issues.

I'm sure there will be other changes discussed before the session is over. Stay tuned.

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Bell County is hopping on the DWI bandwagon for New Years. According to a press release, if you are suspected of driving while intoxicated and refuse a breath test, they are going to obtain a warrant for your blood. Unfortunately, this is not something they just came up with on their own; many other jurisdictions have already implemented this policy. It may not be publicly announced, but it is becoming more common that a refusal to take the breath test is not going to be accepted.

This is being justified as tactic to get drunk drivers of the streets. If you think about that for even a few seconds, it is clear that is not the reason for doing this. It is nothing more than a tactic to obtain more convictions. The driver is already off the street; he has been arrested, and taken to jail. He/she is also off the streets, because their license is taken, and will be suspended for at least 180 days. The only reason to forcibly draw blood is to get more evidence for a conviction. They already have at least probable cause, or they wouldn't have arrested the person.

There's another problem I see with this proposal, which is how many drunk drivers get away while the police officer is taking someone to the hospital to have their blood drawn. They are off the streets for a longer period of time, during which time there are probably people driving under the influence.

I certainly don't advocate driving while intoxicated. Personally, I don't think you have any business driving after you have had anything to drink, even if you aren't legally intoxicated. I don't drink, so it's not something I'm worried about. But I am worried about forcing people to provide evidence to possibly convict them.

The legislature knew people would be hesitant to submit to breath tests, and tried to provide an incentive to take one; your license won't be suspended for as long. They also recognized that in some cases, such as accidents, blood tests should be mandated. They have never approved blood tests in all cases though - if so, the warnings need to be rewritten - do you want to give a breath test or blood or test - you are getting one of them.

I wonder if the new policy is going to include the warning that they are not going to take no for an answer. It doesn't seem fair to me to let someone refuse a test, make them take a blood test, and then suspend the license for the refusal. Even if the blood test was negative, your license could still be suspended for refusing the breath test. At least you should know what is going to happen if you refuse.

Please drink responsibly - not only during the new year celebrations, but all year. But be aware that if you are arrest, you may not really have the right to refuse to be tested.

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