DUI Defense : Criminal Defense

Field Sobriety Tests (FST’s) are tests police conduct on DUI suspects to assess sobriety. Many times the investigating officer has decided to arrest the suspect before administering the tests. In cases such as this, the test is used, not to determine sobriety, but to gather evidence to use against the suspect in court. These tests include the following:

Horizontal Gaze Nystagmus Test

This test describes involuntary jerking or trembling of the eyeball that may occur as a suspect visually tracks a moving object from side to side. Holding an object such as a pen or small flashlight about 12 inches in front of the suspect’s face, the officer moves the object from side to side. The suspect is then instructed to track the movement of the object without moving his or her head. As the test proceeds, the officer watches the suspect’s eyes for the onset of nystagmus. The early onset of nystagmus may be an indication of drinking alcohol. But there are other causes for lateral gaze nystagmus that have nothing to do with the consumption of alcohol. For instance, almost everyone over the age of 40 suffers from nystagmus to some extent.

Walk and Turn Test

The suspect is instructed to take a specified number of heel-to-toe steps along an imaginary straight line, then turn around and take a specified number of heel-to-to steps in the opposite direction. This test has several different aspects, one of which is evaluation of the suspect’s ability to remember and follow instructions. The officer wants to see whether the suspect is able to remember how many steps to take in each direction. For instance, the officer wants to see if the suspect remembers to walk heel-to-toe. The officer also evaluates the suspect’s physical coordination, whether he or she is able to walk a straight line, maintain balance while walking heel-to-toe and turn around.

Standing on One Leg

The suspect is asked to stand with heels together while keeping both arms at the side. Then the suspect is required to raise one foot six inches off the ground while counting out loud until instructed to stop counting. The officer is watching to see whether the suspect is able to stand on one leg without swaying, hopping, or putting the foot down. The officer is also watching to see whether the suspect is able to maintain balance without raising his or her arms.

Finger to Nose Test The officer evaluates the suspect’s physical coordination and ability to follow instructions. The subject is required to stand erect with eyes closed and feet together, and touch the tip of first one and then the other index finger to the tip of the nose. The officer checks and records the extent of the suspect’s success in touching the tip of the nose. Even if the suspect touches the tip of the nose, failure to employ the “tip” of the index finger will be graded “unsatisfactory.” The officer also looks to see whether the suspect remembers to close the eyes. The officer watches to see whether the body sways back and forth during the test and whether there are involuntary tremors of the body or eyelids during the test.