Field Sobriety Tests, what is the difference between fact and fiction?

Thanks to television shows and movies, most people have a basic idea of how field sobriety tests (FSTs) work. Just hearing the phrase “field sobriety test” might make you envision a motorist pulled over to the side of the road, trying to walk heel-to-toe along the yellow line while a stern-looking police officer looks on and the patrol car’s lights flash in the background. Or, perhaps you picture someone trying to touch their nose with their fingertips, balance on one foot or recite the alphabet backwards.

How are Field Sobriety Tests conducted?

In real life, FSTs work a bit differently. Police officers must undergo extensive training to perform these seemingly simple examinations in an exacting yet fair manner that is both actually indicative of a driver’s level of intoxication and will garner probable cause for an arrest. Not all officers are as skilled at administering the tests, though, and the potential for abuse is high. Although field sobriety tests were developed by the National Highway Traffic Safety Administration (NHTSA) to give police officers ways to look for and determine intoxication, studies have shown that these types of tests are not a conclusive indicator of impairment.

More importantly, your performance on a field sobriety test is not objective. Officers perform a variety of tests under very stressful situations and then subjectively evaluate your performance. In fact, you only have to make two mistakes on any part of these tests for the police to deem you have failed and give them reason to arrest you.

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What the police may not tell you about Field Sobriety Tests

It is important to note that in Washington state, officers must advise a motorist that FSTs are voluntary and obtain consent before subjecting a motorist to the tests. Very often, officers will fail to indicate to the motorist that the FSTs are voluntary, and this failure may render the tests inadmissible in court if it can be established that they failed to do so.

We know how to effectively challenge how these tests were administered and their results. For comprehensive DUI defense representation by former prosecutors, contact us today.

We know that a DUI arrest or conviction can wreak havoc on your life. It can affect your reputation and can risk future opportunities. We also know that you want representation that knows all the details regarding how these tests are performed, the latest studies about them and the litigation proving their ineffectiveness. We understand the problems that exist in how field sobriety tests are used and evaluated.

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What are the commonly used Field Sobriety Test techniques?

Washington state, like many other states around the country, doesn’t rely on a single field sobriety test to indicate that a motorist is driving under the influence of alcohol. While individual training programs can differ from jurisdiction to jurisdiction, Washington uses the three standard tests developed by the NHTSA. The three tests are:

Horizontal Gaze Nystagmus Test

The horizontal gaze nystagmus is a reflex action by which the eyes will involuntarily jerk toward a light or motion the eye catches in its peripheral vision. Usually, the response only occurs at a high angle, but if a person is impaired, the reaction will occur at smaller peripheral angles. The NHTSA explains that there are several different things that someone administering a horizontal gaze nystagmus test is looking for that could indicate impairment:

  • Ensuring that the eye is following an object (usually the officer’s finger or a penlight) smoothly
  • If the eyes jerk once they reach a peripheral angle
  • The test subject’s eyes begin to jerk at a shallow peripheral angle (less than 45 degrees)

While the NHTSA’s description is rather technical in nature, essentially the test is designed to judge how coordinated a person’s eyes are when responding to a stimulus. The level of response, though, is a subjective determination made by the officer on the scene. If he or she isn’t properly trained, the results can easily be misleading. There are also several types of legitimate medical conditions that could affect the results of this test, and numerous prescription anticonvulsant and antidepressant medications can cause abnormal retinal responses.

Walk-And-Turn Test

The walk-and-turn test is exactly what it sounds like: having the subject walk heel-to-toe in a straight line, take a number of steps, turn around and then walk back toward the officer. This test is surprisingly thorough, though. It not only checks the subject’s balance while standing, but it also measures:

  • Ability to follow directions (only starting and stopping at the officer’s request, taking a set number of steps, turning in the proper direction)
  • Physical coordination (actually ensuring that the subject’s heels and toes touch properly while walking, not allowing the subject to use his or her arms to stay upright, not stepping off the line during the test)

One Legged Stand Test

The one-legged stand is another seemingly simple task that discloses a surprising amount of information about the subject’s level of impairment to the officer administering the test. If the subject cannot raise one leg and count aloud without lowering his or her foot, uses his or her arms for added balance, sways or hops, he or she might be intoxicated. Of course, balance issues can be caused by inner ear infections, vertigo, physical disabilities and other perfectly innocent reasons.

We are experienced attorneys who will examine all of the facts in a DUI case.

Our Vancouver DUI defense lawyers will carefully evaluate how the police approached you and if they acted appropriately. While field sobriety tests are a helpful and informative tool to police officers trying to determine if a motorist is driving under the influence of alcohol or drugs, they can easily result in a “false positive,” resulting in an arrest for DUI of someone who is not intoxicated.

We know that officers are not looking to see if you will pass these tests, they are actually looking for any evidence they can use against you to substantiate an arrest. They are only looking for errors, so before you consent to a test, you have a right to make an informed decision about how your performance will be judged. Furthermore, these tests are only indicators of impairment, and failing them does not alone mean the driver is actually intoxicated.

What is our process like during a free consultation regarding Field Sobriety Tests?

Because there is so much room for subjective interpretation and legal bars to the admission in court of improperly administered FSTs, if you or a loved one is facing a Washington DUI charge, seek the counsel of a skilled criminal defense attorney to ensure that your legal rights are adequately protected.

Our Washington drunk driving attorneys have extensive experience challenging field sobriety tests as a defense against DUI charges. We know what is at stake in DUI cases. We will work hard to prove FST results are inadmissible. Our goal is always to minimize the consequences of the charge.


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