Most DUI defendants provide breath or blood chemical samples, but in about 20% of these cases, suspects refuse to provide such samples. Additionally, there is no Breathalyzer test for drug impairment. In these cases, Ohio prosecutors must use circumstantial evidence from the Field Sobriety Tests (FSTs) to establish intoxication beyond a reasonable doubt.

FSTs are also important in test cases. The tests usually serve as probable cause for a chemical sample demand. Occasionally, officers skip this important step. More commonly, defendants refuse to perform these tests. In these cases, officers must rely on weak circumstantial evidence, such as an odor of alcohol, to establish probable cause.

The bottom line is that the FST results are almost always an issue in any DUI case. Because it is subject to interpretation, circumstantial evidence is inherently shaky. So, this portion of a DUI case might be a Dayton criminal lawyer’s best opportunity to create reasonable doubt.

Unapproved FSTs

The Romberg balance test is probably the best example of an unapproved field sobriety test. There is almost no evidence that the head back, eyes closed, and arms extended test reliably indicates alcohol intoxication or drug use. Nevertheless, officers frequently administer it, mostly to fatigue defendants before the real tests start. Because it is an unapproved test, many Montgomery County judges either do not admit the results or only admit them for limited purposes. 

However, that is not always the best approach. Romberg’s balance test is premised on the idea that balance requires three things:

  • Vision,
  • Vestibular function (knowing the position of one’s head), and
  • Proprioception (knowing the position of one’s body).

Many officers are either completely unfamiliar with these concepts, or they are at least unable to explain them to jurors. This inability creates the impression the officer is incompetent to testify about FST results and simply wants to railroad the defendant.

Other unapproved tests include reciting part of the alphabet, counting backwards, and trick questions like “What was the year of your first birthday?” Think about that one for a minute.

Approved FSTs

The National Highway Traffic Safety Administration has consistently said that the following three tests are reliable indicators of alcohol or drug intoxication. However, these tests have a number of weaknesses.

  • Heel to Toe Walk (HTW): Perhaps the signature Field Sobriety Test is also known as the walk and turn (WAT) or walking-a-straight-line test. Subjects must walk a straight line heel to toe. During this test, officers look for intoxication clues, like failing to follow instructions and using arms for balance. Conditions often affect this test. For example, flashing squad car lights have a disorienting effect that makes balance difficult.
  • One Leg Stand (OLS): Like the HTW, this test is a divided attention test that measures mental acuity and physical dexterity. Subjects must follow the test directions and then elevate one leg at a 45-degree angle for about 15 seconds. It is almost impossible for anyone with any mobility impairment to complete this test. Furthermore, the OLS is often the last test in the three-test battery. By this time, most defendants are physically and mentally drained.
  • Horizontal Gaze Nystagmus (HGN): The DUI eye test is usually the first test in the three-test battery. Most people have taken this test. If the subject’s pupil moves involuntarily at certain angles, the subject probably has nystagmus, a condition also known as lazy eye. Intoxication is not the only cause of nystagmus. In fact, it is not even the leading cause. Mild childhood brain injuries usually cause this condition.

Recent scientific evidence threatens to drop the HGN test from the approved to the unapproved category. Already, some judges allow the DUI eye test as evidence of probable cause, but not as evidence of guilt or innocence.

Connect with a Dedicated Attorney

Many DUI prosecutions hinge on flawed field sobriety tests. For a free consultation with an experienced criminal defense lawyer in Dayton, contact the Comunale Law Office. We routinely handle matters in Montgomery County and nearby jurisdictions.