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Types of Standardized Field Sobriety Tests in California

Posted on in DUI

San Jose CA DUI-field-sobriety-testing attorneyEven if you have never been pulled over on suspicion of driving under the influence, many people are aware of field sobriety tests from popular television programs such as “Cops,” which shows police pulling over DUI suspects and asking them to walk in a straight line or recite the alphabet starting at a certain letter. While shows like “Cops” can entertain us with failed sobriety tests, a DUI conviction is a serious matter and field sobriety tests are used as legitimate evidence in a court of law. 

What are Field Sobriety Tests?

Field sobriety tests were developed to help police officers determine if a person had consumed enough alcohol that it affected their ability to drive. There are two categories of field sobriety tests: standardized and non-standardized. Most police officers will use a combination of both types to determine impairment, but usually only standardized tests hold up as evidence in court. Standardized field sobriety tests were developed in the 1970s, and their effectiveness has been studied and found to have identified impaired drivers 90 percent of the time.

Horizontal Gaze Nystagmus (HGN) Test

One of the first tests that an officer might use is the HGN test, which measures the involuntary jerking of your eyeball. Nystagmus is the term used for the normal and involuntary jerking of the eyeball. When a person is not intoxicated, nystagmus typically only occurs when the eye is at a high peripheral angle. When a person is under the influence of alcohol, the angle at which nystagmus begins is much less. When the test is conducted, the officer will have the suspect follow a moving object with their eyes in order to observe when nystagmus begins. Intoxicated suspects will typically have difficulty tracking the object as well.

Walk-and-Turn Test

In a walk-and-turn test, the officer instructs the suspect to take nine heel-to-toe steps along a straight line, turn on one foot, and return back to the officer in the same way. During the test, the officer will be looking for indicators such as a lack of balance, capacity to follow directions and the inability to walk in a straight line.

One-Leg Stand Test

During this test, the officer will ask the suspect to stand with one foot about six inches off of the ground while they count out loud to 30. The officer will look for signs of impairment such as swaying, putting the foot on the ground to regain balance, the ability of the driver to follow directions and whether the suspect uses his or her arms to balance.

Contact a San Jose, CA DUI Defense Attorney

If you have been charged with a DUI, you have probably completed one or more of these field sobriety tests. Though the legitimacy of these tests has been debated, they are still used as evidence in courts and will likely be used against you. If you are facing DUI charges because of failed field sobriety tests, you need the help of a San Jose, CA DUI defense lawyer. The Jachimowicz Law Group can help you fight those charges and keep your name clear. Call the office at 408-246-5500 to set up a consultation.






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