Field Sobriety Tests

What are the different types of Field Sobriety Tests?

Here are the most common types of field sobriety tests administered in Utah and what the police are looking for:

Horizontal Gaze-Nystagmus (HGN): the officer will ask the driver to look at an object (usually a pen or finger) that they hold up, close to the drivers face. The officer will then tell the driver to watch the object as they move it. The officer is looking to see how “smooth” the eye movement is. If the eye movement is jerky, this is a sign that the driver may be intoxicated. The driver should not be asked to perform this test if they are facing red and blue emergency lights. Certain medical conditions or contact lenses can also impair test results.

9-Step Walk And Turn: the subject is asked to take a series of steps in a straight line, placing one foot directly in front of the other. After a few steps, the officer will tell the subject to turn, and walk back the same way. There are many ways that the subject can fail this test: walking too soon, taking the wrong amount of steps, stepping off the line, putting a space between steps, losing balance etc. The subject should always tell the officer if they have a physical or medical condition that would impair their test performance.

One-Leg Stand: the officer will ask the subject to stand in front of him, and lift one leg off of the ground, usually for 30 seconds. The officer will watch to see if the subject’s balance seems particularly off. The officer is also looking to see if the subjects internal clock is running fast or slow (which can indicate the presence of different types of drugs). The subject should always perform this test on even ground, and never in high heels.



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