Challenging the Field Sobriety Test Results with Help from a Minneapolis DWI Defense Attorney
The FSTs are always critical in a DWI prosecution. If the defendant provided a chemical sample, the FST results serve as probable cause for the test. Probable cause is a nebulous standard of evidence which is somewhere between reasonable suspicion and beyond a reasonable doubt. If the defendant did not provide a chemical sample, the FSTs must normally serve as circumstantial evidence of intoxication.
The National Highway Traffic Safety Administration has only approved three FSTs. There are actually four approved tests in Minnesota. We examine all these tests in detail below. But first, let’s look at some unapproved FSTs which officers often administer.
Romberg’s balance test, the head-back, arms-extended test, is probably the most common unapproved test. Moritz Romberg, who invented the test in the 1800s, claimed it robbed people of the three things needed for balance, which are:
- Proprioception (knowing one’s body position),
- Vision, and
- Vestibular function (knowing the position of one’s head).
Generally, police officers cannot effectively explain concepts like proprioception and vestibular function to jurors. As a result, many jurors believe that the state is fabricating evidence to railroad the defendant.
Other unapproved tests include reciting part of the ABCs or asking the defendant a trick question, like “In what year was your first birthday?” Think about that one for a minute. These tests have absolutely no scientific basis.
Frequently, officers force defendants to take unapproved tests so they are more fatigued, both physically and mentally, when the real tests start.
You have a right to refuse to perform these tests. The Fifth Amendment is not limited to the right to remain silent. Defendants can also invoke their Fifth Amendment rights and refuse to perform tests.
Horizontal Gaze Nystagmus
During the DWI eye test, officers have subjects track moving objects, like fingertips, moving only their eyes. Involuntary pupil movements at certain viewing angles usually means the subject has nystagmus. But alcohol is not the only cause of nystagmus, a condition also known as lazy eye. In fact, alcohol is not even the leading cause. Many people have a lazy eye, but the symptoms are so mild, they do not know they have it.
Furthermore, the HGN test is only accurate under controlled conditions. Roadside HGN tests are anything but that. For example, the flashing squadcar lights in the background often trigger flicker vertigo, a medical condition.
Walk and Turn
The walking-a-straight-line test is perhaps the signature DWI field sobriety test. Subjects must walk a straight line heel to toe one way, and then walk back the same way. During this test, the officer looks for clues like:
- Starting too early,
- Using arms for balance,
- Taking the wrong number of steps,
- Not walking heel to toe, and
Environmental conditions often affect this test as well. It’s much easier to walk an actual line heel to toe, like a parking lot stripe, than an imaginary line. Darkness also affects the test. So does the type of shoe and the slope of the surface.
Additionally, the state must prove, beyond a reasonable doubt, that the defendant failed the test due to intoxication, as opposed to nervousness, fatigue, or clumsiness.
Much like the WAT, the OLS is a divided attention test which measures physical dexterity and mental acuity. Some scientists claim that intoxicated people cannot multitask in this way. Alcohol impairs brain functions too badly.
For this test, subjects must elevate one leg at about a 45-degree angle and keep it elevated for about thirty seconds. Some intoxication clues include:
- Using arms for balance,
- Not holding the elevated leg still,
- Holding the leg at the wrong angle, and
- Terminating the test early.
People with any mobility impairment cannot hope to complete this test. On a related note, the officer always testified that the defendant “failed” the test, regardless of how well the defendant did. An officer can always find something wrong. However, the jury also decides whether the defendant failed the test, and the jury’s opinion is the only one that counts.
In most states, the FST battery is only three tests. Minnesota is one of the few jurisdictions which includes a fourth one.
Large Breathalyzers, like the ones in use at station houses, have a number of flaws, which are examined below. Portable Breathalyzers are even more unreliable.
For example, these devices are very temperature sensitive. Especially during certain times of the year, Minneapolis weather often changes quickly and with little or no warning. If the portable Breathalyzer was not calibrated according to the current air temperature, the results are probably invalid.
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