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To determine levels of sobriety of a driver must run one or more tests before an arrest for DUI. These tests, which determine the presence of drugs and alcohol in the bloodstream are either sobriety tests or chemical tests. The field sobriety tests used to determine the driver’s mental perception and physical ability to safely operate a vehicle. Such tests monitor if the driver capabilities have deteriorated by alcohol or a controlled substance. Chemical assays employ either a breath test or blood test to determine if the blood alcohol concentration of a driver (BAC) is 0.08% or higher. For drivers under 21, a policy of zero tolerance with any BAC above 0.00% is applied.

Field sobriety test

Before an arrest for DUI, you should perform a field sobriety test or chemical test. The field sobriety test is a preliminary measure used by the forces of order in which the driver may be requested to participate in a DUI checkpoint or a legal traffic stop. With field sobriety tests in general, there are four options:

Stand on one leg:  The suspect must balance on one leg

Horizontal gaze NY stigmas fixed: The officer should guide the eye movement of the suspect with your finger or an object such as a pen

Nine steps walk and turn:   The suspect walking in straight line and makes turns the same way back

Alcohol monitoring device (PAS):   A mobile device that examines the content of alcohol in the breath of the suspect

Chemical testing – Tests driving while intoxicated in Phoenix

Before a lawful arrest, officers of law enforcement should perform a chemical test drivers suspected of driving his vehicle under the influence. In general, there are three types of chemical tests administered by police or licensed professionals who measure the concentration of alcohol in the blood (BAC). These tests include:

  • Breath test
  • Blood Test
  • Urine Test

In general, blood and urine tests for DUI is often associated with extreme situations of DUI and / or suspicion of illegal drug use. In situations where suspects refuse to participate in a chemical test, this can be subject to automatic license suspension.

Ratios of blood alcohol concentration (BAC) in Arizona:

  • Less than 21 years: 0.00% (zero tolerance)
  • 21 years or more: 0.08%
  • Commercial Vehicle Operator: 0.04%
  • Extreme DUI case: 0.15% or more

Those chemical tests that result in a blood alcohol concentration of 0.08% or higher may result in the automatic suspension of the license and DUI formal charge, but does not automatically suggest guilt or conviction. As a citizen, you have certain inalienable rights, including representation by a qualified DUI defense attorney.

Breath test

The demonstration of a misreading of a Breathalyzer test by an agent of the law can have a profound impact on your DUI case. A complete understanding of Breathalyzer tests and any faults that may occur as a result of the test is essential for an effective defense attorney DUI. In some cases, a Breathalyzer test may fail due to equipment malfunction, improper execution or physical or medical condition of a suspect falsely affect test results.

Breathalyzer equipment must be well maintained and calibrated, which can affect test results and the law enforcement officer or licensed professional responsible for the administration of the test must be properly trained in the corresponding process. In some circumstances, the suspects with certain medical conditions may affect the accuracy of the Breathalyzer test.

Blood test for DUI

A blood test can be done by a law enforcement officer or professional license after a DUI arrest by taking a small blood sample from a suspect to determine the blood alcohol concentration (BAC). Based on the results of the blood test, a driver will have been driving under the influence, if your blood alcohol concentration is 0.08% or higher, 0.00% for a minor or 0.04% for a driver in possession of a commercial driver’s license (CDL). A DUI defense attorney expert will know that there are ways to challenge the results of a blood test. The test results may be challenged if the test was not done by a professional trained or qualified, the sample was mishandled or not maintained properly, the test kit had expired or there is a discrepancy over who was in possession of the sample start to finish.

Refusal to breath test IUD

If you refuse to participate in a Breathalyzer test after being arrested on suspicion of driving under the influence, it will automatically suspend your driver’s license. Have the experience of a defense lawyer qualified DUI on your side is essential throughout this challenging scenario and lawyers PLLC Criminal Defense Lawyers can help you through the process.

Accuracy sobriety test

In all tests, there is a margin for error and sobriety tests are no exception. According to the National Highway Traffic Safety Administration (NHTSA), the field sobriety test more accurate – STARE Horizontal NY stigmas- achieved an accuracy of 77% on an evaluation of the test. The test on one leg reached a degree of accuracy of 65% and Walk and Turn test accuracy of 68%. Factors contributing to prove the inaccuracy have been vague instruction of law enforcement officers, suspect’s elderly, overweight and / or nervous fatigue and pre-existing physical or medical conditions.

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