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Breathalyzer, Blood, Urine, and Field Sobriety Tests

Your DUI arrest may start with a traffic stop either for a traffic violation, car issues, or if you are involved in an accident and the police are called. If an officer observes signs of intoxication, you may be arrested for DUI in violation of California Vehicle Code 23152(a). The arresting officer will also conduct pre-arrest and post-arrest tests as part of the DUI investigation.

If you drive in California, the “implied consent” law presumes you have given consent for a DUI breath or blood test when you are arrested for DUI lawfully. There are many issues that arise from taking or not taking these tests, such as evidence used against your in court, invalid test results, and driver license suspensions. Therefore, you need the services of an expert DUI attorney to take over if you are charged with a DUI. At Jonathan Franklin DUI Attorney, we represent clients who have been charged with DUI in the Los Angeles area. We are seasoned in understanding any evidence collected using a breathalyzer, blood, urine, and field sobriety tests.

In the following sections, we will go over all the various tests and the implications of taking such tests.

Breathalyzer Tests

A breathalyzer test is a breath test administered by a law enforcement officer to check the alcohol blood concentration (BAC) of DUI suspects. In California, there are two types of breath tests.

  • Preliminary Alcohol Screening (PAS) Test

A PAS test is given at a DUI checkpoint or after you have been pulled over, but before you are arrested. It is administered using a hand-held instrument, and it is intended to help the police officer determine whether to arrest you. The test is not mandatory. You can decline to take it without consequences except if you are on DUI probation or if you are aged below 21. If you refuse to take a PAS test when you are on DUI probation or under 21, your driver’s license will be suspended whether or not you are convicted of DUI.

Note that a breath test without a warrant does not violate your constitutional rights.

  • Post-arrest Evidentiary Breath Test

It is mandatory for you to take an evidentiary (post-arrest) chemical test if you are arrested for DUI even if you already took a preliminary breath test. In specific counties, the police use Portable Evidential Breath Testing System (PEBT). The PEBT device uses the same technology as the device used for preliminary screening. However, a PEBT can be connected to a printer via Bluetooth or cable, which converts it to an evidentiary unit. Upon arrest, you are entitled to choose either a blood or a breath test. It is advisable to decline a breath test on a PEBT and request a DUI blood test instead. You may not exercise your right to choose a test when:

  • The officer believes you were driving under the influence of drugs; therefore, a blood test is required.
  • You are unable to blow sufficiently for the breath test
  • You are unconscious
  • You need medical care, and the medical facility has no breath testing equipment.

How Title 17 Regulations Affect DUI Breath Tests

Title 17 of the California Code of Regulations governs the procedures that laboratories and law enforcement should follow in collecting and processing DUI breath samples. If any procedure is not observed, your attorney may use the errors to fight your DUI charges. The guidelines are:

  • The testing device should be working properly
  • The device should be calibrated after every ten days or after 150 uses, whichever happens first
  • The person testing must be trained to use that specific device
  • You must be observed for 15 continuous minutes before the breath test is administered
  • During that time, you should not smoke, drink, eat, or put anything in your mouth. You should also not vomit, regurgitate or burp
  • The air must be collected from deep in your lungs
  • The operator should get two breath samples, and the variation between them should be below 0.02g/100ml of blood alcohol
  • The laboratory analyzing the samples must have detailed records of personnel, equipment calibration, and test results.

During your defense, your attorney will be looking for violations of Title 17 regulations such as improperly calibrated or tested equipment, operator error, and failing to keep records. In the records, your attorney will check whether the testing officer:

  • Ensured that your mouth was empty
  • Observed you continuously for 15 full minutes before the test
  • Recorded when the 15-minutes started
  • Attached the mouthpiece to the machine properly
  • Recorded when each blow was made.

Factors that Can Trigger False DUI Breath Test Results

  • Medical conditions such as low carb/ high protein diets, diabetes and gastrointestinal reflux disease (GERD)
  • Residual mouth alcohol that remains in your mouth linings after you use products like alcoholic beverages, cough syrups, and mouthwash
  • Rising blood alcohol if your test is taken within 30 – 45 minutes of consuming alcohol
  • Inhaled chemicals like acetone
  • Interference from radio frequency

Blood Tests

Most people prefer taking a breath test because it is less invasive and faster. However, some people may be unable to blow enough air into the breathalyzer due to medical conditions. Others may be unconscious due to alcohol, drugs, or an accident.

DUI blood tests show the right amount of alcohol in your bloodstream, and they are often considered more accurate than breath tests. Also, a portion of the blood sample is usually saved for retesting in the future.

You are permitted to choose either a blood or a breath test except when:

  • The officer reasonably believes you were driving under the influence of drugs
  • You are unconscious
  • You are in a medical facility that does not have breath testing equipment.

Title 17 Regulations on DUI Blood Tests

Title 17 regulations detail the specific blood testing procedures and general guidelines for testing labs and law enforcement. If any of these procedures are not followed, the accuracy of your blood test may be in jeopardy.

These regulations include:

  • A specified medical professional or technician should draw your blood after your alleged DUI immediately.
  • The draw site should be sterilized with a non-alcohol based product to avoid compromising the sample with external alcohol.
  • The vial should have a preservative and an anticoagulant to prevent clotting and contamination.
  • Reusable equipment should not be kept in or cleaned with alcohol or any other vaporous organic solvents.
  • The integrity and identity of your sample should be maintained across all steps so that the chain-of-custody is undisturbed and recorded.

The Validity of DUI Blood Test Results

California law presumes that your blood test results were obtained properly. Thus, you must prove any suspected violations of Title 17 regulations. Even when Title 17 regulations are not adhered to, the blood test is not automatically invalid. It depends on whether your constitutional rights were infringed.

The police cannot draw your blood against your will if they do not have a warrant except under exceptional circumstances. However, if an officer has a warrant, you can be physically forced to consent to a blood test. An officer will seek a warrant if they believe you caused an accident due to alcohol use or if you are unconscious. Also, refusing a chemical test is not a crime in California. The only consequences are enhanced penalties if you are convicted of DUI and a mandatory suspension of your license regardless of the verdict in your criminal case.

After a blood draw, Title 17 requires that a portion of your blood is retained for one year for independent testing. If you want the sample retested, your attorney has to file a California “blood split motion.” The blood will be analyzed confidentially by any lab of your choice.

In conducting the retest, your attorney will try to establish whether the sample:

  • Showed a BAC lower than .08%
  • Was contaminated or had fermented
  • Was handled or refrigerated wrongly
  • Was affected in any way that may discredit the police lab’s results

How to Fight DUI Blood Test Results

Your attorney can use any of the following three strategies to challenge your DUI test results.

  • File a motion for exclusion of the results from evidence
  • Attack conclusions by law enforcement to get a plea bargain or a case dismissal
  • Demonstrate bad protocol such as a lack of probable cause in your DUI traffic stop.

Urine Tests

The police rarely use urine tests because they are considered the least reliable type of chemical testing. Due to its inaccuracy, the use of urine testing is significantly limited in California. If you are arrested for DUI, you may be given a urine test if a blood or breath test is unavailable.

A urine test must be conducted in strict adherence to Title 17 regulations on collection storage and analysis of the urine sample. These include:

  • You must void your bladder and wait at least 20 minutes before the sample is taken.
  • You must be allowed adequate privacy to maintain your dignity while law enforcement ensures sample accuracy.

There are several reasons why your urine test results may be unreliable. They include:

  • Alcohol is more concentrated in urine than in blood. The concentration of alcohol in urine is about 1.33 times more than in the blood.
  • Your bladder can store alcohol that no longer has an impairing effect.
  • Police and technicians often fail to follow the strict urine test protocols set, leading to frequent errors.

Field Sobriety Tests

These are physical and mental exercises administered by police during DUI investigations. They are tools to help officers decide whether you are under the influence. In California, field sobriety tests are optional. You will face no legal penalties if you decline to take the tests. This is especially important because you can fail the tests for many reasons, even when you are sober.

Types of Sobriety Tests

There are two types of field sobriety tests.

  • Standardized Field Sobriety Tests

Guidelines for conducting DUI field sobriety tests are issued by The National Highway Transportation Safety Administration (NHTSA), a federal agency under the United States Department of Transportation. The agency has validated only three field sobriety tests. These are:

If administered correctly, the tests are considered reliable. They are considered accurate if:

  • They are conducted using standardized procedures
  • Your performance is assessed using standardized clues
  • Your performance is interpreted using standardized criteria

A change in any of the elements will compromise the validity of the tests.

  • Non-Standardized Field Sobriety Tests

The police conduct several field sobriety tests, yet NHTSA does not validate them. There is no proven correlation between tests and DUI impairment. Also, their legitimacy is questionable because their administration varies from one officer to another.

These tests include:

  • The “hand pat” test
  • The “finger-to-nose” test
  • The “finger count” test
  • The “Romberg balance” test

Reasons why Field Sobriety Test Results May be Inaccurate

Field sobriety tests are less accurate than NHTSA claims. Even when conducted properly, they still result in more than 12% false positives. Your attorney can use any of the following reasons to demonstrate why your field sobriety test results may have been inaccurate.

  1. Physical and mental conditions: These include sickness, physical pain, being overweight, mental disabilities, and nervousness.
  2. Movement by the officer: The officer must remain motionless during the tests. Distractive behavior can taint the results.
  3. Unsuitable clothing: Some types of clothing can affect your field sobriety test negatively. They include high heels, tight-fitting shoes, boots, beltless or baggy pants, gloves, and other clothing that may inhibit your performance.
  4. Inaccurate timing: The results are only accurate if the officer uses a watch to time the test, and to properly start and end the timing.
  5. Environmental conditions: Conditions that can invalidate the results include poor lighting, change in weather, a distraction from lights, traffic or spectators, and uneven sidewalk or road surfaces.
  6. Non-standardized tests: These tests have no uniform procedure for administration, and there is no scientific evidence to prove their reliability.
  7. Other reasons for coordination failure: Drugs and alcohol are not the only causes of poor coordination. Other causes include lack of sleep, medication, exhaustion, dehydration, muscle fatigue, and strained muscles.
  8. Vague or wrong instructions: If the officer fails to give you precise verbal or visual instructions, you can challenge the results.

Find a DUI Attorney Near Me

Positive DUI test results do not prove that you are guilty of a crime. Thus, your arrest for DUI does not necessarily have to result in a conviction. If you are in or around Los Angeles, CA, call our Los Angeles DUI lawyer at 323-464-6700. We are well versed with Title 17 procedures and regulations as well as DUI laws. We will use our extensive experience to discredit the results and defend you vigorously.

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Contact Information

Jonathan Franklin DUI Attorney
6777 Hollywood Blvd Ste 508
Los Angeles, CA 90028