Field Sobriety Tests


If you are stopped for suspected drunk or drugged driving, the law enforcement officer will most likely ask you to submit to field sobriety tests.

These tests may be so-called non-standardized field sobriety tests.  They may include reciting the alphabet, counting backwards, or picking a number between two other numbers.

Field Sobriety Tests may also include one or more of Standardized Field Sobriety Tests (SFSTs). The SFST is a series of three tests developed by the National Highway Traffic Safety Administration (NHTSA) and the Southern California Research Institute. Some police receive formal training in giving these tests, which are administered systematically and evaluated according to measured responses of the suspect.

The three field sobriety tests of the SFST are:

The horizontal gaze nystagmus (HGN)

Walk and turn

One-leg stand


Under Michigan law you have the right to refuse any field coordination tasks including any SFSTs. SFSTs can be difficult to pass even for some nondrinking drivers. Also, depending on the police officer’s level of training, the test results may be distorted.

There is no penalty if you refuse to submit to these roadside tests. By refusing the SFST, you are denying the prosecution possible evidence if you subsequently are charged.


As noted, the SFSTs consists of a battery of three tests:

HGN Testing: Horizontal gaze nystagmus is an involuntary jerking of the eyeball which occurs naturally as the eyes gaze to the side. However, when a person is impaired by alcohol, nystagmus is exaggerated and the eyes will often have difficulty smoothly tracking a moving object.

In the HGN test, the officer watches the suspect’s eyes as they follow a slowly moving object such as a pen. The examiner looks for three signs of impairment in each eye: lack of smooth pursuit, distinct and sustained nystagmus at maximum deviation, onset prior to 45 degrees.

It should be noted, HGN may also indicate consumption of seizure medications, phencyclidine, a variety of inhalants, barbiturates and other depressants.

Walk-and-Turn Testing: In both the walk-and-turn test and the one-leg stand test, the examiner is trying to determine how well the subject can listen to and follow instructions while performing what are perceived to be simple physical movements.

Impaired persons often have difficulty with tasks that require their attention to be split between simple mental and physical exercises; therefore, these tests often are referred to as “divided attention” tests. In the walk-and-turn test, the subject is told 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 seven indicators of impairment:

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;

Uses arms to balance;

Loses balance while turning; or

Takes an incorrect number of steps.

One-Leg Stand Testing: In the one-leg stand test, the suspect is asked 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 a 30 seconds. The officer looks for four indicators of impairment:


Using arms for balance;

Hopping; or

Putting foot down.

The fact of the matter is that Standardized Field Sobriety Tests results are subject to challenge by an experienced drunk driving OWI / DUI lawyer.

I am proud to say that I have been NHTSA certified in the administration of SFSTs, having received the same training as law enforcement officials. So, if you have a case and are concerned about your performance on field sobriety tests please submit an on-line form or call me directly at 248-409-0484.

Click Here to Contact Edward Earl Duke

Our Location

180 High Oak Road, Suite 205

Bloomfield Hills, MI 48304

(248) 409-0484 

Field Sobriety Tests
Article Name
Field Sobriety Tests
If you are stopped for suspected drunk or drugged driving, the law enforcement officer will most likely ask you to submit to field sobriety tests. These tests may be so-called non-standardized field sobriety tests.
Duke Law Group