Challenging the DUI FSTs in St. Lucie County
Generally, the Field Sobriety Tests do not matter too much in a DUI case. If the defendant provides a chemical breath or blood sample, and that sample is above the legal BAC limit, the defendant could be guilty as a matter of law.
But in about 20 percent of these cases, DUI defendant refused to provide chemical samples. At that point, the FSTs usually take center stage. In most cases, St. Lucie County prosecutors must use these test results to establish guilt beyond a reasonable doubt. The more a Port St. Lucie criminal attorney can undermine these test results, the less evidence the prosecutor has.
The following three tests are the National Highway Traffic Safety Administration-approved FSTs. Officers may administer other tests, like Rhomberg’s balance test, but these results may only be admissible for limited purposes, if that.
Horizontal Gaze Nystagmus
Most people have taken an HGN test at a doctor’s office. Subjects must track moving objects with their eyes without moving their heads. If their pupils move involuntarily at certain angles, the subject probably has nystagmus.
The DUI eye test may be the most scientifically reliable of the three. But the problem is that alcohol is not the only cause of nystagmus, which is also called lazy eye. In fact, alcohol is not even the leading cause. Many people already have lazy eyes, but the symptoms are so mild, they do not know it.
Furthermore, HGN tests are accurate if they occur under controlled conditions. Roadside HGN tests definitely do not occur under controlled conditions.
Walk and Turn
Conditions also affect the results of the WAT test, which is also called the walking-a-straight-line test. The subject must stand heel to toe, walk a certain number of steps, turn around, and walk back. During this test, officers look for intoxication clues, such as:
- Beginning the test too early,
- Leading with the wrong foot,
- Failure to walk heel to toe,
- Taking the wrong number of steps,
- Using arms for balance, and
- Ending the test too soon.
It is very difficult to walk an imaginary line heel to toe. That’s especially true if the surface is at all uneven or if the test area is not very well-lit. The type of footwear may be a factor as well. It’s very hard to walk heel-to-toe in anything other than athletic shoes. Finally, it’s almost impossible for people with any mobility impairments to walk heel to toe, whether they are drunk or sober.
By the same token, people with mobility impairments usually cannot stand on one leg. At trial, the state must prove the defendant failed the test because s/he was intoxicated, and not because s/he was sleepy, disabled, ill, or clumsy.
Much like the WAT, the OLS is a divided attention test which measures mental acuity and physical dexterity. Supposedly, intoxicated people cannot use both these parts of their brains at the same time.
Since it is similar to the WAT, the OLS suffers from the same deficiencies. Specifically, officers often testify that the defendant “failed” the OLS because of a technicality, like holding the leg at slightly the wrong angle. But jurors have the final word as to who passed and who failed the FSTs.
Team Up with a Savvy Lawyer
The DUI field tests do not conclusively establish guilt. For a free consultation with an experienced criminal defense attorney in Port St. Lucie, contact Eighmie Law Firm, P.A. Convenient payment plans are available.