One Leg Stand

In the One-Leg Stand test, the suspect is instructed to stand with one foot approximately six inches off the ground and count aloud by thousands (One thousand-one, one thousand-two, etc.) until told to put the foot down. The officer times the subject for 30 seconds. The officer looks for four indicators of impairment, including swaying while balancing, using arms to balance, hopping to maintain balance, and putting the foot down.

 

Walk and Turn

In the Walk-and-Turn test, the subject is directed to take nine steps, heel-to-toe, along a straight line. After taking the steps, the suspect must turn on one foot and return in the same manner in the opposite direction. The examiner looks for eight indicators of impairment: if the suspect cannot keep balance while listening to the instructions, begins before the instructions are finished, stops while walking to regain balance, does not touch heel-to-toe, steps off the line, uses arms to balance, makes an improper turn, or takes an incorrect number of steps.

 

HGN Testing

Horizontal Gaze Nystagmus is an involuntary jerking of the eye that occurs naturally as the eyes gaze to the side. Under normal circumstances, nystagmus occurs when the eyes are rotated at high peripheral angles. However, when a person is impaired by alcohol, nystagmus is exaggerated and may occur at lesser angles. An alcohol-impaired person will also often have difficulty smoothly tracking a moving object. In the HGN test, the officer observes the eyes of a suspect as the suspect follows a slowly moving object such as a pen or small flashlight, horizontally with his or her eyes. The examiner looks for three indicators of impairment in each eye: if the eye cannot follow a moving object smoothly, if jerking is distinct when the eye is at maximum deviation, and if the angle of onset of jerking is within 45 degrees of center.

 

Finger Dexterity Test

In the finger dexterity test the suspect must select which hand they will use for the test.  The suspect is instructed to touch the thumb of the selected hand and touch each finger tip starting with the index finger and moving toward the pinky finger. The suspect must count out loud each time their thumb touches a finger (i.e. “1, 2, 3, 4″). As soon as the suspect touches the pinky and counts out loud the number 4 the suspect must immediately execute the test in reverse. The suspect’s thumb must touch the pinky finger tip a second time and work backward to the index finger. The suspect must count backward, “4, 3, 2, 1″. The suspect must perform this routine 3 times.

 

ABC Test

For the ABC Test the suspect will be asked if they know the alphabet.  Once that is established the suspect will be asked to start with a certain letter and end with a certain letter from the alphabet, i.e. start with C and end with W.  The suspect should not sing the alphabet and this test requires a suspect to listen to and follow instructions to perform a simple task.

 

Counting Backwards Test

The counting backwards test requires the suspect count backwards starting with a certain number and ebd with a certain number, i.e. start with 69 and count backwards to 53.  You are looking for indicators such as whether the suspect is unable to follow oral instructions, unable to count correctly without skipping or repeating a number, unable to maintain your balance while counting, and/or are unable to complete the test.