Arizona DUI Lawyer & Attorney : Koplow & Patane Law Firm : Arizona DUI Defense

Kim Smith of the Arizona Daily Star has reported that a Tucson City Court judge has ruled prosecutors cannot use the results of breath tests administered to 49 people scheduled to be tried before him on DUI charges. Her article states:

If other judges agree with Judge Thomas Berning, prosecutors could find it hard to prosecute thousands of other DUI cases locally and statewide. "I'm optimistic the other judges will agree with Judge Berning. It's a well-written decision," said defense attorney Joe St. Louis.  "This could be really big."

Last year, law-enforcement officers across Arizona began administering breath tests to suspected drunken drivers using a new machine called the Intoxilyzer 8000, St. Louis said. Almost immediately, defense experts realized the machines were sometimes providing "weird" or inexplicable results, St. Louis said.

In order to figure out what was going on, the experts said they needed to see the machines' "source card" or software. The software would also enable the experts to determine whether the results were accurate and reliable, St. Louis said.

 "It's a Sixth Amendment issue," St. Louis said. "Defendants have the right to cross-examine and confront their accusers." Defense attorneys began demanding the software from prosecutors, arguing they have a constitutional right to the information. Because prosecutors revealed they didn't have access to the software, Berning ordered the machine's manufacturer, CMI, to provide the software.

When CMI refused, defense attorneys filed a motion on behalf of 49 defendants asking Berning to dismiss their cases completely, suppress the results of the breath tests or assess monetary damages against CMI. Prosecutors told Berning the software is "proprietary" and can't be ordered disclosed, and the law doesn't allow for the evidence to be suppressed. They also argued they had given defense attorneys everything they had in their possession. Late last week, Berning ruled the results of the breath tests should be withheld from jurors.

Prosecutors will still, however, be able to provide jurors other evidence that could prove a defendant's guilt, such as the results of field-sobriety tests, St. Louis said. Although she can't comment on pending litigation, city prosecutor Laura Brynwood said she plans to appeal the judge's decision.

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Arizona law enforcement often uses breath-testing devices to determine the blood-alcohol concentration (BAC) of a person suspected of DUI.  The Intoxilyzer 8000 is commonly used in Maricopa County.  When a person is suspected of DUI, he is generally requested to blow twice into an Intoxilyzer; this is referred to as “duplicate breath testing.”

The Department of Public Safety (DPS) has issued regulations for duplicate breath testing, which it defines as “two consecutive breath tests that immediately follow a deprivation period, agree within 0.020…of each other...”

In addition, the Department of Public Safety defines a deprivation period as “at least a 15-minute period immediately prior to a duplicate breath test during which period the subject has not ingested any alcoholic beverage or other fluids, eaten, vomited, smoked or placed any foreign object in the mouth.”  Breath-testing experts have stated that the deprivation period is critical to the breath-testing process. (See Kurt Dubowski, “Quality Assurance in Breath-Alcohol Analysis,” Journal of Analytical Toxicology, Vol. 18, October 1994.)

Commonly referred to as “quality assurance” measures, the DPS regulations seek to prevent any factors from affecting the breath sample.  Putting something in the oral cavity prior to the test could certainly change the results. Thus, law enforcement officials must prevent anything being put into a DUI suspect’s mouth prior to the breath tests.

When examining the breath test record, the starting and ending times of the deprivation period must be noted.  A 15-minute time span wherein a person does not put anything in his mouth is not sufficient; the deprivation period must “immediately” precede the first breath test.

The record must not show any gap between the deprivation period and the first breath test. Moreover, the police officer who conducted the deprivation period should be questioned. If he cannot account for any gap in time, then the test fails to comply with DPS regulations and may be inadmissible.

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Law enforcement's primary method for determining if a person is driving under the influence of alcohol is a chemical test.  That is, a police officer will take a sample of a susect's blood  or breath.  The chemical test assumes that the composition of everyone's blood is the same.  Specifically, the test assumes that all people have the same hematocrit level.  However, this assumption is incorrect.

The hematocrit level, or packed cell volume, is a measure of the proportion of blood volume that is composed by solids.   Whole blood is composed of solid particles in liquid.  the solid portion of whole blood contains: (1) white blood cells; (2) red blood cells; and (3) platelets.  The liquid portion of the blood is known as plasma. 

In this manner, if a man has a hematocrit level of  .51, then his whole blood consists of 51% solids and 49% liquids (plasma).  This solid to liquid ratio will effect the outcome of a blood alcohol concentration test.  The reason is the liquid portion of the whole blood, the plasma, contains water.   Alcohol is more susceptible of being dissolved in water than is the solid portion.  Consequently, the liquid portion of the whole blood will have a higher concentration of alcohol than the solid portion.

Stated another way, the higher the hematocrit level (thus the less liquid) in the blood, the greater the concentration of alcohol in the liquid portion of the blood.  Ultimately this means several people with the same amount of alcohol in their body, but different hematocrit levels, will have different test results. 

Men and women have different average hematocrit levels.  A normal hematocrit for a man is 45 (plus or minus 7%). Women have a normal hematocrit level of 42 (plus or minus 5%).  There are numerous other factors that can effect a hematocrit level.  However, a person's hematocrit is not proportional to body size. 

Hematocrit ranges primarily effect breath alcohol testing. This is because in blood testing the blood is mixed with an internal standard (such as N-Propranol which has similar structure to Ethanol, but has a different number of carbons).  In sum, varying hematocrit levels expand the range of accuracy in blood alcohol concentration testing.  This expanded range of accuracy can be a valuable defense for a person accused of driving under the influence alcohol (DUI).

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Challenging the reliability of a chemical test result is usually essential to effectively defending a DUI case.  In order to accomplish this task a thorough understanding is needed of the types of chemical testing used in Arizona and the scientific principals behind those tests. Here are the three types of chemical tests used by Arizona law enforcement:

1. Breath Testing
2. Blood Testing
3. Urine Testing

Blood and breath testing are by far the most common.  Moreover, there is a trend in Arizona law enforcement moving towards blood as the primary testing method.  However, some police agencies such as the Department of Public Safety appear to be staying primarily with breath testing.  Urine testing is utilized mostly in cases where it is suspected that a person is under the influence of drugs.  Urine testing is seldom used in our state for blood alcohol testing.  Below is a summary the potential defenses for cases involving both breath and blood alcohol testing. 

BREATH TESTING DEFENSES

In order to know what defenses may be available to an attorney, an understanding of the breath alcohol testing process is required.  Breath testing is based on the scientific principal of Henry's law (also referred to as Henry's coefficient).  Henry's law was conceived by the English scientist William Henry. The principal provides in a closed container over time some of the molecules in a liquid will travel into the gas above the liquid. The amount of molecules that travel into the gas will be directly proportional to the number of molecules in the liquid.  Henry's law assumes a constant temperature and a closed system.  Consequently, all the factors that may influence Henry's law may also effect the results of a breath test.

The instrument used to apply Henry's law to breath testing is an Intoxilyzer.  In Arizona, most agencies now use the Intoxilyzer 8000.  The instrument is manufactured by a company named CMI.  The instrument is supposed to take a sample of the subject's lung air and use the principals of Henry's law to estimate a person's blood alcohol concentration.

Her are some of the challenges to evidentiary breath testing:

• Range of Accuracy
• Temperature Changes
• Lack of a Deprivation Period
• Radio Frequency Interference
• Failure Keep Calibration Records
• Partition Ratios
• Lack of Warranty
• Forced Agreement of Tests
• Breathing Patterns
• Mouth Alcohol
• Hermatocrit Levels
• Calibration Errors
• Source Code Disclosure

 BLOOD TESTING DEFENSES

Similar to breath testing, blood testing also relies on the principals of Henry's law.  However, a different instrument is used to test the blood sample.  Most forensic laboratories use a headspace gaschromatograph.  Headspace refers to the space in a vial above the sample where the gas portion is located. Headspace analysis is the analysis of what is present in that gas. In its simplest terms, gas chromatography attempts to separate and identify what is in that head space gas. 

Some of the attacks that can be made on this blood testing process are:

• Margin of Accuracy
• Improper Tube Inversion
• Chain of Custody
• Contamination of Sample
• Proper Site Cleaning
• Lab Testing Errors
• Expired Materials
• Serum Samples
• Failure to Follow Manufacturer's Instructions

While blood testing can be an accurate and precise measure of a person's blood alcohol concentration, it is not perfect.  Even under ideal conditions, there will still be a range of accuracy regarding test results.  However, conditions are not always ideal.  When basic scientific protocols are not followed the reliability of the test comes into question.

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