The Initial Observation and Contact: An arrest for DUI usually begins when a law enforcement officer comes in contact with a driver while the car is moving. Law enforcement will watch for certain behaviors before they stop a driver under suspicion of DUI.
For example, if a driver is driving in an unusual manner, law enforcement may stop the driver. Unusual driving may include making wrong turns, failure to signal correctly, speeding, driving too slow, swerving, or failure to stop at a signal or stop sign. Once the law enforcement officer stops the driver, he or she will monitor the driver's behavior. Law enforcement will look for signs of intoxication such as bloodshot eyes, slurred speech, smell of alcohol on the driver's breath, and open containers in the vehicle.
The Fourth Amendment to the United States Constitution protects citizens from unlawful searches and seizures; In other words, the officer must have a legal reason for stopping the driver. If the stop is illegal, then the evidence gathered from the illegal stop may be suppressed – this would include all of the officer's observations and any chemical test results.
Thus, the reason for the initial stop is very important and must be analyzed by an experienced DUI defense attorney. DUI Defense Attorney Manuel J. Barba is an expert in DUI Defense and can evaluate your case to determine if any Fourth Amendment violations occurred.
After stopping the car, if the officer has reason to suspect that the driver is driving under the influence of alcohol and/or drugs, the officer may ask the person to perform field sobriety tests.
Field sobriety tests are voluntary and no person is required to perform them (unless you are on probation for a prior DUI conviction) - however law enforcement officers won't tell you that the tests are voluntary.
If a person agrees to perform the field sobriety tests, he or she will be evaluated by the officer on how he or she performs and reacts during the testing. Standardized Field Sobriety tests are validated, which means that the tests must be administered in a precise way for the results to have any validity. If the officer fails to administer the test exactly as they are designed to be administered, then the results are compromised and mean very little.
Often times the officer will have the driver perform field sobriety test that are not standardized. It requires a DUI defense attorney that is an expert in field sobriety tests to evaluate which tests were given to a driver, whether the tests were administered correctly or not, and what the results mean, if anything.
DUI Defense Attorney Manuel J. Barba is a nationally recognized Standardized Field Sobriety Test Instructor, having completed the National Highway Safety Administration (NHTSA) and International Association of Chiefs of Police (IACP) DWI Detection Standardized Field Sobriety Testing Instructor Program and is an expert on field sobriety test administration and evaluation as well as the protocols for drug recognition evaluations (DRE). Attorney Manuel J. Barba teaches classes training other lawyers on Standardized Field Sobriety Tests throughout the United States.
Determining Alcohol Level:
Alcohol testing is an attempt by the law enforcement officer to determine how much alcohol is in a driver's bloodstream at the time of driving. If an alcohol test shows a result of 0.08% or higher, a driver is presumed to have violated the law (Vehicle Code 23152(b)) – driving with a blood alcohol concentration of .08% or more. It is important to note that the alcohol test is supposed to determine the driver's blood alcohol concentration at the time he or she was driving the car, and not after the fact.
Due to alcohol absorption issues, as well as other factors, there can be a significant difference between a driver's blood alcohol concentration at the time of driving and the time the actual test is given, which sometimes occurs an hour or more later.
The two most common tests that law enforcement officers use to determine a person's blood alcohol concentration is a breath test (the driver blows into a device) and the blood test, where the driver's blood is drawn for analysis. Various factors such as gender, amount of alcohol consumed, weight, type of alcohol consumed, time of consumption, time of test, and food consumption can directly impact the reliability of the results of these tests.
During a breath alcohol test, the person blows into a breath analysis machine. Although there is a relationship (partition ratio) between a person's breath alcohol concentration and the alcohol concentration in their blood, that relationship varies by a number of factors and is not constant.
The breath alcohol testing machines assume that the relationship (partition ratio) between breath alcohol and blood alcohol is always the same for all people at all times; but in reality, that relationship varies widely thus making breath alcohol results often unreliable.
In addition, the science of breath alcohol testing assumes that the subject has fully absorbed all of the alcohol ingested. This means that all of the alcohol the person drank is no longer in their stomach or small intestine – and all of the alcohol has absorbed into the blood stream. If a person has not fully absorbed the alcohol that they drank, then breath testing is not reliable because the breath testing machine will overstate the result by 2-3 times.
Studies show it can take anywhere from thirty minutes to three hours or more for a person to absorb all of the ingested alcohol, depending on when the person last ate, what they drank, when they drank, etc. Thus, if a person drank a few drinks, then drove, and then was stopped by an officer and blew into a breath machine, the breath machine might show a result of .12 when in reality the person has a blood alcohol concentration of .04 -.06%, which is obviously less than .08% – the legal limit.
Through a blood alcohol test, a person's blood alcohol content can be determined if the analysis if the sample was done correctly. Compared to a breath test, a blood test is a more accurate method to determine a person's blood alcohol concentration; however it is far from perfect.
During a blood alcohol test, blood is drawn from a person's vein, usually from the arm, and then it is analyzed using a very complicated process known as gas chromatography. If the blood test analysis reveals the person's blood alcohol concentration to be 0.08% or greater, that person is presumed to be in violation of the law (VC 23152(b)) – driving with a blood alcohol concentration of .08% or more.
However, the reliability of the blood test result is commonly an issue due to issues such as contamination of the blood sample during the blood draw, handling and storage of the blood sample, insufficient preservative, insufficient anticoagulant, defective sample tube, bacteria, fermentation, accuracy of the gas chromatography process, as well as other issues.
DUI defense attorney Manuel J. Barba is an expert in breath alcohol and blood alcohol testing as well as alcohol absorption and burn-off issues. To successfully defend your DUI case, you need an attorney with this specialized knowledge.
Call the Law Offices of Manuel J. Barba today at (760)770-3377 to discuss your DUI case.