Field Sobriety Evaluations or "Tests"

Utah Field Sobriety Tests Overview

Field sobriety tests (FSTs) are tests designed to determine whether someone is under the influence of alcohol or drugs. When police officers suspect that someone is driving under the influence, they are trained to administer field sobriety tests before they make an arrest for DUI. There are three standardized field sobriety tests established by the National Highway Traffic Safety Administration (NHTSA) which are used in Utah:

• Horizontal Gaze Nystagmus (HGN)
  
• Nine Step Walk and Turn
  
• One Leg Stand
  

Horizontal Gaze Nystagmus

Horizontal Gaze Nystagmus is an involuntary jerking of the eye that happens naturally when someone moves his eyes from side to side. When a person is under the influence of alcohol, this jerking becomes more exaggerated. This happens because the small muscles that control the eyes have a more difficult time controlling fine eye movements, so the eyes will jerk or skip instead of moving smoothly from side to side. Also, when the eyes are looking all the way to one side, they will bounce sideways instead of staying still.

When an officer performs the horizontal gaze nystagmus test, he will hold a pen or a finger in front of your face and will watch your eyes as he moves it from side to side. If your eyes cannot smoothly follow the moving pen, or if your eyes cannot stay still while looking to the side, or if the jerking starts prior to a 45 degree angle, then the officer will usually decide you are over the legal limit and arrest you for DUI.

However, the HGN test is far from perfect, and many other things may cause HGN, such as medications, head trauma, flashing lights, or other medical conditions. By itself, the HGN test is never enough to prove that a person is under the influence of alcohol. Also, unless the test is performed exactly how it is designed, then the results of the test are invalid.

Many officers forget parts of the test, or get impatient and skip some parts. A good DUI lawyer will examine each part of the test and challenge any results that could be invalid.

 

Nine Step Walk and Turn

The Nine Step Walk and Turn test is a “divided attention” test which is designed to measure whether a person can do a mental exercise and a physical exercise at the same time. The test operates under the assumption that a person who is not intoxicated can easily do the test when he or she is not under the influence.

To perform the Walk and Turn test, an officer will ask you to take nine steps, heel to toe, in a straight line, then turn around, and take nine steps in the opposite direction, all while counting out loud. The officer will watch you as you walk in a straight line to see if you make any mistakes. If you begin before the officer tells you to start, raise your arms for balance, do not touch heel to toe on every step, do not turn correctly, step off the line, take the wrong number of steps, or count incorrectly, the officer will use these as “clues” that you are under the influence. If the officer notices two or more of the “clues” he will usually decide that you were driving under the influence of alcohol or drugs.

The Walk and Turn test also has many weaknesses. Many people who have zero alcohol in their system will fail the Walk and Turn test for other reasons. Unless you are paying perfect attention to all of the instructions, it is easy to forget exactly how to do the turn, and if your feet are separated by even an inch, it will be seen as a clue of DUI. Also, most people will raise their hands naturally while walking in a straight line slowly, which has nothing to do with alcohol.

One Leg Stand

The One Leg Stand test is also a “divided attention” test, used to test whether someone can balance and count for an extended amount of time. This test also operates under the assumption that a person who is not intoxicated can successfully complete the test when he or she is not under the influence.

An officer will ask you to stand with one foot six inches off the ground and count out loud by thousands (one one thousand, two one thousand, etc.) without putting your foot down. He will watch you for approximately 30 seconds to see how you count and how well you keep your balance. If you count wrong, sway, hop, use your arms to balance, or put your foot down, the officer will count these as “clues” of being under the influence of alcohol. If he notices two or more clues, the officer will usually conclude that you are DUI.

Like the other tests, the One Leg Stand test is often wrong. Many people who are not intoxicated have difficulty completing the test. Unless you are paying complete attention to exactly how the officer wants you to do the test, and then you concentrate very hard to do exactly what he says, it is natural to use your arms to balance, and most people will naturally sway while standing on one foot. Also, many past and current medical conditions can make it difficult to perform the test as directed.


Bostwick & Price, P.C. Utah DUI Defense Attorneys

The law firm of Bostwick & Price, P.C. has experienced Utah DUI defense attorneys ready to fight for your rights and defend your DUI arrest. Our Utah DUI defense team includes a former Utah police officer who has years of real world experience with Utah DUI arrests, enforcement and education. This unique experience, training and education of our Utah DUI defense team, combined with our law firm’s desire to fight for your rights provides you with the Utah DUI defense team you deserve. www.bostwickprice.com