Driving under the influence (DUI) endangers everyone using the road, including drivers and passengers, pedestrians, and fellow motorists. Alcohol and drugs severely reduce a driver’s ability to stay safe on the road, leading to accidents, injuries, and deaths. To eliminate these risks, law enforcement officers administer DUI tests, specifically breath and blood tests, that accurately measure a driver’s blood alcohol concentration (BAC) and decide if the driver is impaired. These assessments act as preventative tools used to identify impaired drivers who have elevated BAC over legal limits and thereby remove impaired drivers from the road to protect the public.
Breath tests involve a breathalyzer device that estimates BAC through a quick, noninvasive procedure. If an officer suspects drug impairment or wants more precise data, they can administer a blood test. However, both methods ensure accountability to those who operate a vehicle while impaired.
If you are charged with DUI or are in a situation where police officers require a breath or blood sample, it is important to know your rights and what you can do to defend yourself. DUI laws have serious penalties, including fines, license suspension, and possible jail time if you are convicted of a DUI-related offense. In this situation, it is best to have an attorney. Contact the San Diego DUI Attorney today for experienced legal representation from DUI lawyers who will protect your rights and walk you through every phase of your case.
Driving Under the Influence Under California Law
A DUI offense in California occurs when you drive with a blood alcohol concentration (BAC) over the legal limit or while impaired by drugs. Vehicle Code 23152 establishes standards for BAC levels and impairment according to the type of driver and substance used.
The legal BAC limit for drivers 21 and older is 0.08%. Any BAC level at or above this level impairs judgment, motor skills, and reaction time, resulting in a significant risk of an accident. If your BAC reaches this level, law enforcement will conclude you are impaired. Officers often measure BAC at the scene through breath tests, but they can administer blood tests for a more precise reading if they suspect you are under the influence of drugs.
The commercial driver BAC limits are different, as are those for minors. Both present a unique risk. The BAC limit is lower at 0.04% for commercial drivers. This lower limit acknowledges the risk these drivers pose because they drive large vehicles that can cause serious damage should an accident occur. For drivers under 21, California has a zero-tolerance policy. This means their BAC level is set at 0.01%. This strict threshold reflects the state’s commitment to lowering rates of incidents caused by underage drinking, which are more likely to occur with inexperienced drivers who may be overwhelmed by any unexpected situation.
California law also prohibits driving under the influence of any drug, whether prescription, over the counter, or illegal, that impairs driving ability, in addition to alcohol impairment. Driving becomes hazardous because many drugs affect how you react. You could experience:
- Slowed reaction times
- Impaired coordination and
- Reduced focus
If an officer suspects drug impairment, they often watch the driver’s behavior and use field sobriety tests to detect symptoms. A blood or urine test can confirm the presence and type of drug involved.
Driving under the influence of alcohol and drugs is also forbidden. Impairment from combining substances is often more than the sum of their parts. Drivers can be more affected than they would be by either substance alone. These cases are assessed by drug recognition experts, whose job it is to detect signs of impairment. They then provide their findings in court as evidence.
California effectively enforces its DUI laws with checkpoints, specialized officer training, and public awareness campaigns. These efforts focus on deterring DUI incidents.
Establishing Probable Cause
Under the law, you can only be tested for alcohol if law enforcement officers have probable cause to believe that you are driving under the influence of alcohol or drugs. Probable cause refers to an action or activity that officers observe that would make them believe you were impaired. This requirement protects your rights and ensures DUI tests only happen when justified.
Various observations of erratic driving patterns, like sudden stops, swerving, or driving at excessive speeds, can lead officers to reasonably suspect a problem. Further, traffic violations like running a red light or driving without using blinkers may also contribute to that officer’s assessment. Moreover, slurred speech, bloodshot eyes, or the strong odor of alcohol that the officer notices further indicate that impairment may well be likely.
Officers often perform field sobriety tests to see if you can coordinate your body and your cognitive function before administering an alcohol test. Failing the sobriety tests gives officers a basis for probable cause to request a more accurate blood alcohol concentration (BAC) measurement.
Probable cause is usually necessary in most cases, but there are exceptions, like DUI checkpoints. Officers can stop a vehicle at these checkpoints for a short time without a specific suspicion of impairment. However, even at checkpoints, officers must still see signs of impairment before administering a breathalyzer or blood test.
Under California’s implied consent law, you must comply if an officer believes there is probable cause and requests a breath or blood test. If you operate a vehicle in the state, you agree to submit to chemical testing if an officer lawfully requests it. Refusing a chemical test can result in immediate administrative penalties, including an extended license suspension or more fines.
Note: If an officer tests you without probable cause, it will violate your rights, and the evidence against you could be thrown out in court. If you are charged with DUI, you can challenge the validity of the test and have the evidence thrown out if you believe the officer failed to establish probable cause properly.
Tests Police Officers Rely on to Determine BAC
Police officers rely on the following tests:
- Field sobriety tests (FSTs)
- The Preliminary Alcohol Screening (PAS) test
- Blood and urine tests
These tests help determine if a driver is impaired.
- Field Sobriety Tests (FSTs)
Police officers use field sobriety tests (FSTs) to determine your level of impairment. Based on their assessment, they will decide if further testing is required. Usually, these tests are administered before the officer goes on to a Preliminary Alcohol Screening (PAS) test.
FSTs involve various physical and cognitive tasks that evaluate your coordination, balance, and overall ability to drive safely. The tests conducted by these officers gather critical information about your condition before deciding whether further testing is needed.
If an officer detects you could be impaired, he/she may pull you over and ask you to perform FSTs. The common tests that measure particular mental and physical capabilities are:
- The walk-and-turn
- The one-leg stand and
- The horizontal gaze nystagmus
The Walk-and-Turn Test
In the walk-and-turn test, you will be asked to walk a straight line, taking several steps in one direction, turning on one foot, and returning in the same way. Police officers test for balancing, coordination, and following instructions. The officer will watch to see if you follow a straight line, stick to the step count, and do not appear to lose your balance. You will fail the test if:
- You deviate from the line,
- You fail to complete the steps
- You stumble or fail to follow instructions
The One-Leg Stand
Under this test, you balance on one leg and count aloud for around 30 seconds. This exercise tests your stability and coordination. Nodding is another sign of instability that officers watch for, including hopping or placing your foot down to reposition yourself. It helps them determine if you can stay steady under physical stress, which can indicate impairment.
The Horizontal Gaze Nystagmus
When officers administer the horizontal gaze nystagmus test, they check on your eye movements. In this test, an officer has you watch a moving object, usually a pen or their finger, and follow it with your eyes. They watch for involuntary jerking of your eyes, which could be a sign of being intoxicated. This test measures how well you can smoothly track the object and shows whether you have trouble focusing or noticeable eye jerking.
All the above tests produce results that give officers an idea of how intoxicated you are. If your performance on the FSTs raises red flags, the officer could take the next step and administer a PAS test. This test measures your blood alcohol content (BAC) by breath analysis, so you will get a more accurate assessment of how intoxicated you are.
- PAS Test
A Preliminary Alcohol Screening (PAS) test is an important way for law enforcement to determine if a driver has been drinking. The breathalyzer test measures blood alcohol content (BAC) using a non-invasive method that reads the alcohol in someone’s breath. The PAS test delivers immediate results that officers can use to make an informed decision as to whether or not further testing, like a more accurate breath or blood analysis, is required. It is an important early step in DUI investigations.
Generally, you have the right to refuse a PAS test in most jurisdictions. However, there are consequences should you refuse. Declining the test will result in your driver’s license being suspended if you are under 21. This is in line with the strict zero tolerance on underage drinking and driving. Likewise, if you are on probation for a previous DUI offense, refusing to submit to a PAS test could lead to probation revocation and additional penalties, complicating your legal circumstances.
There are risks in refusing a PAS test. Implied consent laws are many states’ way of saying that if you choose to drive, you consent to chemical testing if law enforcement suspects you of impairment. Refusing a PAS test could subject you to automatic administrative penalties, including license suspension or revocation. Further, if an officer has reasonable suspicion of your behavior or how you were driving, that officer can arrest you without your consent to the PAS test. You need to know your rights and the potential legal consequences of your choices during a traffic stop.
PAS tests are not always reliable or accurate. Several factors can affect the result, including:
- Recent dental work
- Some medical problems, or
- The type of device used to test
- Mouth alcohol from recent drinking or oral hygiene products
- Deviations from the test due to differences in device calibration and maintenance
Remember, the PAS test functions merely as an initial screening tool to help officers decide if there is enough to warrant further investigations.
You could contest the results in court if you think the PAS test was administered incorrectly or the testing device was faulty.
- Blood and Urine Tests
If law enforcement officers believe that the results of an initial breath test warrant additional examination, they will request blood and urine tests to obtain a precise measure of a given individual’s blood alcohol concentration. Officers also rely on these tests to detect the presence of certain controlled substances. These tests should conform to the strict guidelines of Title 17 of the California Code of Regulations. The regulations aim to guarantee the reliability and integrity of the results. Some of them include the following:
Qualified Professionals Should Administer the Tests
Blood testing needs to be administered by a qualified professional, the drug recognition expert (DRE). These individuals must be fully qualified to conduct the test to minimize the risk of contamination or procedural error, which would skew the result. Good technique is critical. Any misstep can ruin the sample, and the result can be inaccurate, with profound legal implications.
Proper Preservation of Blood Samples
Another important aspect of the testing process is preserving the blood sample. Once collected, the sample must be mixed with preservatives that prevent fermentation. Fermentation can artificially inflate the BAC reading to produce misleading results regarding the level of intoxication. By using appropriate preservatives, laboratories can maintain the sample’s integrity, thereby maintaining the integrity of the sample and accurately reflecting your BAC at the time of testing.
It is equally important to maintain the correct temperature of the blood sample for accuracy. Your sample should be stored at a stable temperature to prevent chemical reactions that might change its composition. Temperature fluctuations can degrade the sample or affect the final results. Laboratories preserve the sample’s reliability for testing by making sure the sample is at the correct temperature while in storage and transportation.
Proper Maintenance of Blood Drawing Tools and Testing Equipment
Collection equipment must be sterilized. Blood drawing tools must be cleaned and sterilized using non-alcohol-based agents. This ensures that no alcohol is introduced into the sample, as this can skew the results and paint an inaccurate picture of your BAC.
Furthermore, testing equipment requires regular maintenance and calibration. Calibration is defined as modifying equipment to obtain accurate measurements in accordance with known standards. Not regularly calibrated and maintained equipment increases the risk of errors and possible actual wrongful accusations or penalties from false or incorrect data.
Contesting DUI Breath and Blood Tests
Facing DUI charges based on breath and blood tests can be overwhelming. Nevertheless, your DUI lawyer can challenge the results of these tests. A strong defense strategy hinges on identifying the issues that may affect the accuracy and reliability of the evidence against you. Your attorney could challenge the evidence in the following ways:
- Scrutinizing Test Administration Procedures
One key approach is to examine how the procedures conducted during breath and blood tests are carried out. Strict protocols apply, so law enforcement officers must follow them when administering the tests. Your attorney can argue that the results should be inadmissible if they do not.
For example, if the breathalyzer was not correctly calibrated before use, the readings may not accurately indicate your blood alcohol content. Your attorney will also request maintenance and calibration records to ensure the device is in working order.
- The Personnel Administering the Tests Was Not Qualified
The reliability of the results depends on the qualifications of the people performing the tests. Trained professionals must do both breath and blood tests. Your attorney could argue that the test results should not be trusted if the officer who administered the test was not properly trained or certified. It can also investigate the credentials of the officer involved to see whether he committed procedural lapses.
- There Was Potential Contamination of the Blood Sample
The potential for contamination during blood sample collection provides an avenue for scrutiny and grounds for challenging the evidence against you. Blood must be drawn under sterile conditions, and the equipment used must be sterilized with a non-alcohol-based agent. Lapses in maintaining these standards can jeopardize the sample and consequently read BAC inaccurately.
For instance, if a piece of equipment to be tested was not cleaned properly, it could introduce substances that could lead to an artificially elevated BAC reading. So your attorney can point out these problems and question the credibility of the test results.
- Improper Sample Preservation
Proper preservation of the blood sample is also essential for maintaining its integrity. After collection, the blood sample must be mixed with appropriate preservatives to prevent fermentation. False elevated BAC readings can result from fermentation. Your attorney will argue that the results are invalid if proper preservation methods were not followed. The test outcome is significantly affected by any alteration to the sample.
- Temperature Control Maintenance
Title 17 requires that the blood sample be stored at the right temperature. This requires the lab to properly control its temperature systems because blood samples are only accurate if stored at specific temperatures. Changes in the sample’s composition could occur if not stored correctly, and the results would become less reliable.
Your attorney can investigate how your blood or urine samples were handled. Any evidence of mishandling is grounds to challenge your DUI charges.
- Your BAC Was a Result of a Medical Condition
Any medical conditions that might have affected the test results are a key consideration. Certain medical conditions can cause BAC levels to be elevated or negatively impact the accuracy of the breathalyzer. For example, people with diabetes can produce acetone, which can cause false results. Your attorney can document your medical history and residency through medical documentation and expert testimony that your health might have rendered you unable to provide accurate results.
- Inconsistencies in Your Case
If your attorney can find inconsistencies in the case against you, then your attorney can challenge the prosecution’s evidence. It may also involve reviewing the timeline of events, introducing witness statements, and identifying any potential police bias that could have impacted your case. Reviewing every aspect of the case, your attorney can build a comprehensive defense to protect your rights.
- Blood Split Motions
You can also use blood-split motions for your defense strategy. The legal approach involves requesting that the blood sample be divided into two and tested separately. This can give you a second confirmation of the BAC results, which could be potentially valuable, especially if you contest the first results.
If the split sample gives you a different result, it can aid your defense and raise reasonable doubts about the validity of the original readings.
Find a DUI Attorney Near Me
The breath and blood test results become critical components in any DUI charge, and they often seem overwhelming at first. However, these tests can be challenged because of possible inaccuracies related to the method used in testing your BAC and the qualifications of the personnel. An experienced DUI attorney understands these subtleties and can fight the results with evidence that supports your defense.
You need specialized knowledge to navigate the complex legal landscape of DUI charges. A reputable DUI attorney will know how to leverage any weaknesses in the prosecution’s case to build a defense strategy that suits your case. They will also help you explore other options, like plea agreements or diversion programs, that will reduce the consequences you could face if you are convicted.
If you face DUI charges, you need professional assistance. Contact the San Diego DUI Attorney today. Our committed attorneys are ready to help guide you and provide the legal expertise you will need to achieve the best possible outcome. Contact us at 619-535-7150 for a free case evaluation.
