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Types of Sobriety Tests for Drunk Driving

The police use three types of field sobriety tests to decide whether they have probable cause to arrest a suspect they pull over for DUI. Legal experts advise against ever taking the tests, which are not mandatory under the law.

The field sobriety tests gauge a person’s ability to stand on one leg, walk with agility, and supposedly determine whether the suspect’s eyes move normally. Authorities say these tests also help police determine whether a person is mentally impaired. If they can’t follow directions, the cops say, they may be drunk or high.

If you take the drunk driving tests, the prosecution also may try to get permission from a judge to use the test results against you in court if you get charged with driving under the influence.

It is not legally mandatory to take the field sobriety tests if an officer asks you to, and there are supposed to be no legal consequences if you refuse. Some will say the tests are designed to make the person being tested fail. 

It is important to point out the difference between field sobriety tests and chemical tests. Chemical tests measure the amount of alcohol in the blood. 

Chemical tests are mandatory

Be aware that a chemical test of the breath, blood, or urine is mandatory under the law if the officer arrests you. You can lose your driver’s license longer and face a higher fine if you refuse a chemical test if you’ve been arrested. And it may hurt your case to refuse a chemical test.

If you are not under arrest, you need not submit to any tests, whether chemical or a field sobriety test (FST).

The officer who pulls you over likely will not tell you that the field sobriety tests are not mandatory. He may even say he will arrest you if you don’t take the test. You should politely but firmly refuse to take any roadside agility tests, as they are also called.

The 3 types of FSTs

The three standardized FSTs approved by the U.S. government are:

  1. The Horizontal Gaze Nystagmus Test: The officer asks the suspect to follow an object with his eyes. If the driver jerks his eyes around a lot and has difficulty following the object, it may be considered evidence of intoxication. Nystagmus can happen for more than 40 reasons besides intoxication.
  2. The Walk-and-Turn Test: The officer asks the suspect to walk in a straight line, heel to toe. The test is meant to gauge a driver’s ability to maintain his balance and remember the officer’s instructions. The test divides a suspect’s attention between mental and physical tasks. 
  3. The One-Leg-Stand Test: The driver must stand on one leg for 30 seconds and maintain balance.

For all three tests, the officer tries to determine if the person can follow and carry out the somewhat detailed instructions for the tests, keep his balance without using his arms, and perform the tests in a sober manner. 

There are other field sobriety tests, but these three mentioned above comprise the standardized tests validated by the National Highway Traffic Safety Administration.

Officers can arrest without a test

If the person has difficulty doing the tests well, the officer may consider it evidence of intoxication and arrest the driver for DUI. Of course, the officer can arrest a driver for DUI whether or not the person takes the field sobriety tests. So why take the test if you can be arrested anyway? The tests are so subjective that you should just refuse to take them.

Let us help if you face DUI

Just as police and prosecutors use tests to try to convict you, an experienced DUI attorney can use the tests to help you. Defense lawyers can shed doubt on the officer’s ability to properly do an FST or say he misused the test. They can shed doubt on the validity of the tests themselves.

A skilled attorney can call into question the results of a Breathalyzer or other chemical tests or the credentials of the lab technicians. A lawyer may be able to find discrepancies in the arrest, or enter into evidence testimony or video evidence that contradicts the officer’s story.

A lawyer can help you mount a defense saying your rights were violated if it’s true that they were. Also, if the accident involved injuries, a lawyer may be able to get the charge reduced from a felony to a misdemeanor and help you avoid all kinds of legal trouble, including prison.

Just because you have been arrested for DUI, don’t think a conviction is a certainty. Let a law firm put together a defense that can reduce your charges or penalties, or perhaps even get you acquitted.

H Law Group Online

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