In order for scientific evidence to be admissible in a Texas court, the party wishing to put such evidence before the court must show that (1) the underlying scientific theory is valid, (2) the technique applying the theory is valid and (3) the technique was applied properly on the date in question. This is known as the Kelly standard.
When applied to alcohol breath testing it means that who ever operates the breath test machine is doing so in accordance with the Texas Breath Alcohol Testing Regulations. These regulations can be found in Title 37 of the Texas Administrative Code, Part 1, Chapter 19, Subchapter A.
Rule 19.4 governs the proper method for administering a breath test to a person arrested on suspicion of driving while intoxicated. Rule 19.4(c) deals specifically with the what the breath test operator has to do in order for a breath test to be valid.
The Texas Breath Alcohol Testing Program Operator Manual states that the operating temperature of the reference sample device ("simulator") is 34 degrees C plus or minus .2 degrees C. The manual states that the "operator may verify the correct temperature by observing the thermometer on the front of the device."
The simulator has a heating element to warm the alcohol solution to the proper temperature, a thermostat to maintain that temperature and a stirring paddle to ensure an even temperature inside the jar.
The simulator is used "to verify the accuracy and calibration of the [intoxilyzer]." The breath test machine analyzes the alcohol concentration inside the simulator as a part of every breath test.
In Scillitani v. Texas, No. 14-08-00430-CR, (Tex.App.--Houston [14th Dist.] 2011), the Houston Court of Appeals was asked to determine whether or not the breath test operator was required to verify the temperature of the solution inside the simulator.
The court rejected Mr. Scillitani's argument on the grounds that nowhere in the breath test regulations does it state that the breath test operator must verify the temperature of the solution inside the simulator.
According to Rule 19.4(c)(4), in order for a breath test to be valid, the result of the machine's analysis of the solution inside the simulator must be within .01 g/210 L "or such limits as set by the scientific director." That rule did not change when the breath test regulations were updated effective March 2006.
There's a problem with the court's conclusion, however. The simulator is supposed to be a tool used to calibrate the breath test machine. The breath test machine sucks in a certain amount of vapor from the headspace gas inside the simulator. That vapor is then analyzed to determine its alcohol concentration and to compare it with the predicted value. But if the solution is outside the designated tolerance, can we trust that the machine is calibrated properly?
If you take a jar of water and alcohol and seal it, Henry's Law* says that the alcohol concentration in the headspace above the solution should be the same as the alcohol concentration of the solution. Heat up the solution and the molecules will become more active and the alcohol concentration will rise. Reduce the temperature and the opposite will occur.
Even if the vapor from the simulator is within .01 g/210 L of the predicted value, if the temperature is outside the required tolerance, questions must be raised about whether the breath test machine is calibrated correctly. Is the actual value different from the predicted value because the machine isn't working? Is it because the simulator solution wasn't mixed properly in the first place? Is it because the sample chamber is contaminated in some way? These are all legitimate questions that can't be answered without knowing the actual temperature of the simulator solution.
Now let's think about this logically for a second. Why would the manual produced by the Department of Public Safety and used to train both breath test operators and technical supervisors state that the temperature of the simulator solution must be within a certain tolerance of 34 degrees C if it wasn't necessary to verify that temperature? Why not just rely on the machine's analysis of the vapor from the simulator? Why put a thermometer on the simulator?
If the question is whether or not a breath test was conducted properly, then shouldn't we be looking at the Texas Breath Alcohol Testing Program Operator Manual, the book used to train breath test operators, to make that determination?
* Henry's Law is remarkably similar to the Hermetic concept of "As above, so below." You can also find it in the so-called Emerald Tablet, the foundation of the alchemists' belief system. The breath test machine conducts its own form of alchemy by turning a measurement of length into a volumetric measurement.
These are the musings, ramblings, rantings and observations of Houston DWI Attorney Paul B. Kennedy on DWI defense, general criminal defense, philosophy and whatever else tickles his fancy.
Showing posts with label texas breath test manual. Show all posts
Showing posts with label texas breath test manual. Show all posts
Monday, August 1, 2011
Wednesday, August 20, 2008
Loss of normal use...

1. Loss of the normal use of one's mental faculties due to the introduction of
alcohol, a drug, a controlled substance, or a combination thereof, into the
body;
2. Loss of the normal use of one's physical faculties due to the introduction of alcohol, a drug, a controlled substance, or a combination thereof, into the body; or
3. Having an alcohol concentration of .08 or higher.
There are two training manuals that are a must have for any lawyer who practices DWI defense in Texas - DWI Detection and Standardized Field Sobriety Testing (published by NHTSA) and the Texas Breath Alcohol Testing Program Operator Manual (published by the Texas Department of Public Safety).
Both of these manuals may be used to impeach the state's witnesses on the subject of "loss of normal use." A criminal defense attorney who knows what he's doing can cross-examine the state's witnesses with these manuals through the "learned treatise" exception to the hearsay rule.

According to the breath test manual, "[i]t is not the alcohol in the peripheral areas of the body which impairs a person's coordination, but the alcohol concentration in the CNS (central nervous system) tissue." This seems to indicate that it's not the concentration of alcohol in a person's breath that is critical -- it's the concentration of alcohol in a person's central nervous system (brain, brain stem and spinal cord) that is critical.
The breath test manual goes on to state that "[t]he first effect of alcohol is the impairment of judgment." That's because "[a]lcohol affects the brain in reverse order of how the brain develops." In other words, the higher level brain functions, such as judgment, logic and reason are affected before the lower level brain functions, such as breathing and digestion. According to the breath test manual, "[p]sychomotor skills are motor actions (physical faculties) proceeding directly from mental activity."
The NHTSA manual states that alcohol "doesn't affect a person until it gets into their central nervous system, i.e. the brain, brain stem and spinal cord."
This is important because the manuals the state uses to train its experts tell us that alcohol affects one's mental faculties before it affect's one's physical faculties. Thus, evidence indicating the citizen accused had the use of his mental faculties at the time of driving can be used to refute the state's argument that if a person performs poorly on the police coordination exercises, he must be intoxicated.
Now when you ask the arresting officer or the state's breath test expert whether alcohol affects one's mental or physical faculties first, and he tells the jury alcohol affects them both equally, you can pull out your manuals and read the training material that contradicts his "expert" testimony. But in order to do that, you have to know what's in those manuals.
If you're defending citizens accused of DWI, and you don't want to commit malpractice, you need to get those manuals ASAP.
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