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Common Policing Errors for a DUI Stop

If you have been arrested for driving under the influence (DUI) in San Diego County, the experienced defense attorneys at San Diego DUI Attorney can greatly improve the chances of a favorable outcome to your case. Our lawyers are specifically qualified to review your case, determine errors of fact in the police report and produce a reduction in charges, or have the case dismissed outright.

Our specially trained lawyers at San Diego DUI Attorney will thoroughly review your case to assess errors that may have occurred during your arrest, rights that may have been violated and the validity of the facts listed in the police report. The combination of our extensive experience and thorough review of your case could lead to the charges against you being reduced or dismissed.

Common errors made by police during DUI traffic stops and arrests include:

  • Stopping a motorist without probable cause.
  • Police officers are required to have “sufficient probable cause” before making a traffic stop (California Penal Code Section 836a). If these criteria was not met in your traffic stop, it may have been an illegal stop and your case could be dismissed.
  • Failure to read the Miranda Rights.
  • It is a constitutional right to have your Miranda Rights read to you by the arresting officer at the time of arrest. These rights include your right to remain silent, your right to hire an attorney, and your right to have a public defender assigned to you if you cannot afford an attorney. If the arresting officer failed to read the Miranda Rights to you, any information that you divulged prior to the arrest becomes inadmissible as evidence against you.
  • False interpretations of field sobriety tests.
  • Field Sobriety Tests (FST) are used by arresting officers to determine your level of impairment if you are suspected of a DUI. These tests are intended to evaluate your balance, coordination and motor skills. The judgment of the officer administering the tests will determine whether you pass or fail. There are many factors that can contribute to errors in administering the FST. 

Some examples are:

1. Dim lighting

2. A slippery walking surface 

3. Poorly worded instructions from the officer 

4. Error in the officer’s assessment of your coordination

5. Unknown medical conditions at the time of testing

Although California regulates breath tests, there are instances and errors that can lead to a "false positive". If your breath result shows a blood alcohol level greater than California legal limit, this could be due to several things. It is important to have a skilled attorney explore false positives that could lead to your case being dismissed.

False positives can be due to:

1. Contamination of the breath sample

2. Officer operation errors. Some mistakes that people administering a breath test can make are not checking that your mouth is empty before the test and not properly attaching the mouthpiece to the machine.

3. Poor record keeping. The person administering the test must observe and record you continuously for 15 minutes before administering the test and then record the time that each "blow" was made.

4. Improper calibration of the device.

5. Medical contains unknown at the time of testing. Fasting, Hypoglycemia, high protein/low carbohydrate diets and diabetics have been known to trick breath tests When someone is on a low carb diet, their body will burn its own fat and produce ketones. Ketones are converted into acetone and a breath test can confuse alcohol with acetone. Fasting also causes the body to produce acetone that can fool a breathalyzer. Diabetics emit ketones due to their condition, which are often mistaken by breathalyzers.

6. Residual Alcohol in the mouth can lead to a breath test reading a higher alcohol level than the person actually has in their system. If you recently drank cough syrup, gargled with mouthwash containing alcohol, or drank alcohol right before the test, your breath test could come back abnormally high. Residual alcohol can stay in the mouth for up to 20 minutes. 

Our lawyers will carefully scrutinize each aspect of the FST to ensure that it was administered fairly and we will determine whether extenuating circumstances may exist, calling into question the officer’s interpretation of the FST.

As previously mentioned, there is room for error with a California DUI breath test. You can decline a preliminary alcohol screening breath test (PAS) unless you are under 21 years of age, or are on probation from a previous DUI. It is uncommon for police officers to let you know that you do no have to take the PAS test. 

The PAS test is given roadside, on a handheld breathalyzer. This test is given before the driver is arrested. After the driver is arrested, and evidentiary air test on the breathalyzer will also be given.  This evidentiary air test usually takes place at the police station or possibly a mobile police checkpoint.

There are certain rules that police must adhere to when administering DUI breath tests. Some of the rules are:

1. The person administering the DUI breath test must be trained properly.

2. Only a California–approved DUI breath test device may be used.

3. The person administering must continuously observe you for 15 minutes before they administer the test. During those 15 minutes, you cannot smoke, eat, drink, burp, or vomit.

4. The breath test device must be correctly calibrated. California law states that a breath testing devise is calibrated after ever 150 use or every 10 days, whichever occurs first. 

5. The person administering must keep proper records during each stage of the breathalyzer calibration and test.

6. The person administering must obtain two breath tests and the results can be no different than 0.02 g per 100 milliliters of blood alcohol. It is okay for the person to ask you to "blow" more than two times to get the correct breath samples. 

7. The person administering must get the breath sample from deep in your lungs.

If you are arrested for a DUI, you then must take a "chemical test" if asked.  Often officers will ask you to take a chemical test if they suspect you are under the influence of drugs, as well as, or rather than alcohol.

If you refuse to take a chemical test after you are arrested, it can result in enhanced penalties if you are convicted of a DUI and a minimum one year license suspension.

A common question is, is it is better to choose a blood test or DUI breath test. Both tests can work to your advantage and disadvantages in different instances.

A DUI breath test will not measure your blood alcohol directly. The breath test mathematically converts the alcohol in your breath into the amount in your blood, which is why the sample must be taken from deep in your lungs. This conversion is called a 'partition ratio". 

Breath samples cannot preserve, so it is difficult to verify the test at a later time. This can work to your benefit if an attorney questions the accuracy of the test.

There are certain medical conditions that can prevent you from taking a breath test.

Some of those conditions are:

1. Emphysema

2. Asthma

3. Unconsciousness

If you have been charged with a DUI, our attorneys can help you. Call us for a free consultation and we can begin to discreetly and respectfully investigate your case. Our attorneys are specifically trained and exclusively handle these types of cases in San Diego and Orange County.

The experienced criminal defense attorneys at San Diego DUI Attorney can assess your case, build a defense and help reduce charges or avoid a conviction following your DUI arrest. The entire staff at San Diego DUI Attorney specializes in DUI and Criminal Defense Law, serving clients in Orange County, San Diego, Vista, El Cajon, Oceanside, Chula Vista and other San Diego County communities.

Contact our office today at 619-535-7150 for a FREE DUI consultation.

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