Finding The Flaws In A Field Sobriety Test

  • Feb 27 2019

If you have been charged with a DUI after failing a field sobriety test you may think there is no use fighting the charges. After all, would the cops be doing these tests if they weren’t foolproof indicators of intoxication? But the truth is field sobriety “exercises” — they aren’t even allowed to be called “tests” in court — are a sham.

Field sobriety exercises are not scientific indicators of intoxication. At best, they are a tool the police can use to extend the amount of time they are able to detain and observe a driver they suspect is impaired without actually arresting them. At their worst they are an embarrassing trap that tricks sober drivers into appearing intoxicated.

What are Field Sobriety Tests?

In the late 70s/early 80s the federal government’s National Highway Traffic Safety Administration (NHTSA) developed a standardized set of exercises it claimed would help law enforcement officers across the country crack down on drivers suspected of driving under the influence. Despite a lot of skepticism from the scientific community about their accuracy, the tests were widely adopted.

Most if not all of the dozens of law enforcement agencies in Miami-Dade County use the three most popular field sobriety exams — horizontal gaze nystagmus, walk and turn, and the one-leg stand.

Horizontal gaze nystagmus (HGN) is an involuntary jerking of the eyes that occurs as the eyes move to the side. When a person consumes alcohol, nystagmus is exaggerated and may occur at lesser angles depending on the degree of impairment. This is what the police are looking for when they ask you to follow their finger or a light as they move it back and forth.

The Walk and Turn and One-Leg Stand exercises require a person to listen and follow a long set of confusing instructions while performing seemingly simple physical movements. People who are impaired have difficulty with divided attention tasks, so listening and moving around is challenging.

If the driver has a physical disability or ailment that prevents him or her from being able to complete one of these exercises he or she may instead be given the finger-to-nose test, a counting test, or the Rhomberg Alphabet test. (You may recall newspaper reports about Tiger Woods struggling with the Rhomberg test when he was charged with a DUI in 2017.)

The officer must administer the exercises and record his or her observations about the driver’s performance. Based on his or her observations, the officer may have probable cause to arrest the subject.

The officer’s observations, and any video recordings of the encounter, may be admitted as evidence in court. However, the officer is not allowed to give an opinion on whether someone “passed” or “failed” a particular exercise because the results are highly subjective, not scientific.

Common Flaws & Failures

Although the tests are “standardized” and have been in use for decades, they are in no way perfect indicators of intoxication. Sober people fail these exercises ALL THE TIME. And drunks who are familiar with the tests have been known to study the tests and practice for them. They are simply not reliable.

Plus they are often administered incorrectly, and the results of an incorrectly administered test must be thrown out. At Valiente Law, we successfully challenge charges stemming from faulty field sobriety tests all the time.

We look for (and often find) evidence that the field sobriety tests:

  • Were improperly administered because the officer was not properly trained.
  • Were biased by the officer’s opinion about the driver.
  • Cannot be accurate because the environment, weather, or lighting skewed the results.
  • Should be thrown out because the driver has a physical impairment that could mess with the results. People who are older, overweight, wearing dry contacts, or hard of hearing may not be accurately tested.

We also help women who are asked to remove their shoes and complete the exercises in bare feet challenge the results because such a jarring experience can skew the results.

Don’t Let Junk “Science” Destroy Your Driving Record

If you were arrested for driving under the influence because you failed the field sobriety tests, you should consider contesting the charges. Even if the cops have video of you falling over or otherwise making a fool of yourself trying to follow their directions, there is a good chance that it was the field sobriety exercises that were illegal that day, not your actions.

Posted in: DUI