When is Chemical Testing Conducted in a DUI Case?

  • May 26, 2017

    Breath tests are the most common form of testing you’ll encounter when a police officer suspects you of driving under the influence in Los Angeles. Whatever results that the breathalyzer shows determine what kind of charge may apply, and how the legal system will treat you. That’s why you need a well-trained Los Angeles DUI Attorney to contest the results, which aren’t always so ironclad as they seem.


    The First Time

    The Preliminary Alcohol Screening Test, or PAS, is the first time that an officer will request a chemical test. You breathe into a machine that the officer carries with him, which then measures your blood alcohol level.

    Yet most drivers don’t realize that the PAS test isn’t mandatory, and failure to take it doesn’t mean an immediate suspension of your license. However, the officer will give the opposite impression, because he’ll use the PAS test to establish probable cause for your arrest.

    Just remember that refusing the PAS won’t count in your favor, especially if the officer has other reasons to suspect you’ve been drinking, like the smell of alcohol on your breath. From the officer’s perspective, the PAS is simply the first step in laying the case for a DUI conviction.

    The Second Time

    Once you’re arrested, handcuffed and transported to the police station, an officer will probably ask you to take a second chemical test. You may choose between a blood, breath or urine test. By law, you must take this test, but the officer won’t necessarily force it on you. He knows that, under state law, your refusal will bring severe consequences, like a one-year license suspension.

    Challenging The Test

    Experienced Los Angeles DUI Lawyers understanding the importance of timing in fighting a chemical test. Though the test can capture your blood alcohol content at a certain time, it can’t pinpoint if your BAC levels are rising. This issue is important, since your attorney may argue that when the officer arrested you, your BAC didn’t rise to the .08 percent level that a DUI charge requires.

    The timing of any test that an officer gives isn’t the only issue your attorney will consider in preparing a DUI defense. Other relevant factors include how much food, if any, you consumed when you drank, and whether you’re a diabetic. In both cases, the test could pinpoint you as a DUI offender, even if you didn’t drink a large amount of alcohol.

    Other Possible Outcomes

    Like other devices that police officers use, breath machines are often vulnerable to false readings, improper care or administration, and incorrect calibration. If no other defense seems viable, your attorney will focus on attacking these inconsistencies. The prosecutor may then start discussing a plea deal in your case, or show a willingness to dismiss it.

    Prosecutors have varying motives for such decisions. He may believe that the case is too weak or error-laden to bring. Your attorney may also succeed in getting the court to suppress the text result, which is usually the centerpiece of a DUI case. Without a result, the prosecutor may not find it worthwhile to proceed with the case.

    The timing of chemical tests and the issues they raise is just one of many reasons why you need a seasoned Los Angeles DUI Attorney to handle your case. The sooner you hire one, the more likely that you’ll avoid the negative impact of a DUI conviction on your license, liberty, and pocketbook.

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