Field Sobriety Tests

When a driver is pulled over on suspicion of DUI, there is a good chance the police officer is going to ask the driver to take one or more field sobriety test. Field sobriety tests are conducted on the side of the road to help an officer determine if a driver is too intoxicated to be operating a vehicle. These tests challenge a driver’s physical coordination, mental alertness, reaction time, and ability to follow instructions.
Although there are many different field sobriety tests for an officer to choose from, most officers in Phoenix ask drivers to perform at least one of the following six tests:

Walk and Turn: The subject takes nine heel-to-toe steps along a line, turns, and takes nine heel-to-toe steps back. The officer is looking to see if the accused can keep their balance, follow instructions, begin early, stop during the test, leave space between heel and toe, step off the line, or lose balance while turning.
 
Standing on One Leg: The accused is instructed to stand with heels together, arms at the side, then raise one leg six inches off the ground while counting out loud until the officer allows the accused to stop. The officer is looking for raising of the arms, swaying, hopping, putting the foot down, inability to stand still, body tremors, muscle tension, and any statements made by the accused during the test.
 
Finger to Nose: The accused is instructed to stand with heels together, eyes closed, and standing straight. The officer will then instruct the accused to bring the index finger to the tip of the nose. The officer is looking for body sway, body tremors, eyelid tremors, muscle tension, or any statements made by the accused to support a finding of intoxication.

The Rhomberg Balance Test: The accused assumes a position of attention, closes their eyes, tilts back their head and counts to 30. At this time the officer is looking for the inability to stand still or steady, body or eyelid tremors, opening of the eyes to maintain balance, swaying, muscle tension, or statements made by the accused. The officer is also testing the accused’s sense of time, which will usually be slower in the case of alcohol or depressants, or fast in the case of stimulants.

Horizontal Gaze Nystagmus Test: This test is performed when the officer attempts to estimate the angle at which the eye begins to jerk ("nystagmus" is medical jargon for a distinctive eye oscillation). The officer will position an object (such as a pen) 12 inches away from the driver’s face. If nystagmus occurs sooner than 45 degrees, it theoretically indicates a blood-alcohol concentration over .05%. The smoothness of the eyes tracking the penlight (or finger or pencil) is also a factor, as is the type of jerking when the eye is as far to the side as it can go.

Preliminary Alcohol Screening: The officer uses a portable breath device to determine the presence of alcohol in the system.

Why Do I Need a Phoenix DUI Lawyer?

These tests are supposedly designed to check "divided attention," a critical skill in operating a motor vehicle. However, there are many people who, for many innocent reasons, cannot perform these tests to the officer's satisfaction, and pay the price with a DUI arrest.  In addition, these tests are scientifically unreliable and highly inaccurate. The outcome of the test is very subjective, as it is based entirely on the discretion and personal opinion of the officer who is administering the test.

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