For the walk-and-turn test, the officer asks the driver to take nine steps, heel-to-toe, along a straight line, turn on one foot and return nine steps in the opposite direction. During the test, the officer looks for seven indicators of impairment.
The HGN test measures the steadiness of your eyes while you follow an object with your eyes. Officers often use their finger or perhaps a pen for this test because they can easily see your eyes while providing an object for you to follow. This particular test has a total of six possible indicators (three for each eye).
Generally speaking, you are not legally required to take these tests, regardless of how many times an officer may ask you to do so. The tests are meant as an investigative aid to the police officer.
4. One-Leg Stand Test Clues. In order to gauge whether a driver is intoxicated, law enforcement officials will typically watch for four major “clues†of intoxication during the administration of the one-leg stand test. Keeping these clues in mind, officers will then give one point for each clue that is spotted.
Divided attention task. Neuropsychological tests related to the ability of a subject to perform two different tasks simultaneously.
Nystagmus is a vision condition in which the eyes make repetitive, uncontrolled movements. These movements often result in reduced vision and depth perception and can affect balance and coordination. These involuntary eye movements can occur from side to side, up and down, or in a circular pattern.
To conduct the test, the police officer is supposed to check the driver's eyes to see that the pupils are of equal size and to see that the eye is able to track an object as it is moved side to side at eye level.
There are a total of 8 clues the officer is looking for. The police officers are taught that if the person demonstrates 2 or more clues on this test or fails to complete it, then there is a 68% accuracy in determining the suspect's blood alcohol content is above 0.10.
In the following test one eye is look at a time. After the medical assessment is completed then the officer moves on to the HGN tests to evaluate impairment. IMPORTANT: The HGN Test should take approximately 88 seconds. If done too fast the test may have been improperly done.
Nystagmus occurs when the part of the brain or inner ear that regulates eye movement and positioning doesn't function correctly. The labyrinth is the outer wall of the inner ear that helps you sense movement and position. It also helps control eye movements. The condition can be either genetic or acquired.
PURPOSE: Law enforcement officers trained as Drug Recognition Experts (DRE's) routinely assess an impaired driver's ability to converge the eyes to the bridge of the nose. Lack of Convergence (LOC) will be present with intoxication due to certain drugs other than, or in addition to, alcohol.
Nystagmus is a medical condition in which the eyes move involuntarily, often shaking back and forth. These involuntary movements may be horizontal, vertical, or sometimes even rotational. The movements may be very subtle, very prominent, or somewhere in between. They can be fast or slow.
There are eight clues associated with the walk and turn test. Two can be assessed in the “instructional stage†(starts too soon, looses balance) and the remaining six in the†walking stage†(misses heel to toe, steps off line, uses arms to balance, stops while walking, too many steps, improper turn).
Nystagmus has an incidence rate of at least 1 in 1,000 people in the general population and is the most common form of visual impairment among school aged children. The condition affects both men and women, although some forms of nystagmus, such as X-linked infantile nystagmus may be more common in boys.
Everything you need to know about NystagmusNystagmus is a condition whereby a person suffers with involuntary, uncontrollable eye movements. The condition can often make someone's eyes look like they are shaking, moving quickly either from side to side, up and down, or in a circular motion.
If you refuse to submit to any chemical test -- breath test, blood test, or urinalysis -- this refusal typically will be admitted in court as "consciousness of guilt" and result in an automatic suspension of driving privileges in most states.
In fact, no one can pass the Field Sobriety Tests, because they are not designed to be passed. You may be thinking, “I know someone who took the Field Sobriety Tests and was allowed to drive home without getting a DUI. Doesn't that mean they passed?†Well, no.
How a DUI Lawyer Can Challenge Field Sobriety Tests
- Stand on one foot while counting.
- Walk a straight line, heel to toe for a specific distance.
- With arms stretched out, touch your finger to the tip of your nose.
- Repeat the alphabet from Z to A.
- Nystagmus or Horizontal/Vertical Gaze Test.
Original research revealed that this test, when properly administered and scored, was only 65% accurate in determining if someone was under the influence of alcohol. If you remember, the Walk and Turn test was only 68% accurate. Thus, the OLS test is the least accurate field sobriety test of the three.
Roadside field sobriety tests ("FSTs") are commonly used by police officers in DUI investigations to determine whether a driver is under the influence of alcohol. Fourth, field sobriety tests are irrelevant and, in fact, designed for failure.
The 3 tests that make up the SFST are the horizontal gaze nystagmus (HGN), the walk-and-turn, and the one-leg stand tests. Developed in the 1970s, these tests are claimed to be scientifically validated, and are admissible as evidence in court in a majority of states including California.
According to government studies, the walk and turn test is 68% accurate in determining whether a driver has a blood alcohol concentration above . 10. Hence, nearly one out of three people who fail the test are not drunk driving.
Distinct and sustained nystagmus will be evident when the eye is held at maximum deviation for a minimum of four seconds. People exhibit slight jerking of the eye at maximum deviation, even when unimpaired, but this will not be evident or sustained for more than a few seconds.
Horizontal Gaze Nystagmus Test (HGN)The officer checks for three clues in each eye, which gives six clues for this test. The clues are: lack of smooth pursuit of the eyes, distinct and sustained nystagmus at the eyes' maximum deviation and nystagmus starting before the eyes reach 45 degrees.
Each clue of the six clues in the HGN test has two passes plus the two passes of the preliminary check for equal tracking resulting in the total of 14 passes for a HGN test.
Steps:
- Remove glasses/ask if wearing contacts (note type of contacts)
- Position feet together and place hands at side.
- Keep head still during test. Follow stimulus with eyes only.
- Position stimulus 12-15" from person's face in front of the subject's nose slightly above eye level.
The HGN test is one of three field sobriety tests that are approved by the National Highway Traffic Safety Administration (“NHTSAâ€) as providing an accurate indication of driver impairment.
