Roadside Field Sobriety Tests for DUI – What You Probably Don’t Know

August 08, 2014

sobriety testDriving under the influence of alcohol or drugs is illegal in the United States. When you are caught, you will surely face legal charges that might lead to revocation of license or worse, you might end up in jail. Law officers conduct and implement roadside field sobriety tests to examine if a person is intoxicated. Once an officer suspects you for drunk driving and there is a clear indication that you are intoxicated, you may have to undergo a field sobriety test.

Knowing how all of these tests work and how they are implemented is essential. At least, you know how things are done and you know what to avoid especially when you are driving.

What Are the Features of a Standardized Field Sobriety Test

SFST also known as the Standardized Field Sobriety Test follows certain guidelines set forth by the National Highway and Traffic and Safety Administration (NHTSA). There are three tests for SFST.
Horizontal Gaze Nystagmus (HGN) Test

One of the clear indicators when a person is drunk is his eyeball movement. Nysgtagmus is characterized by the involuntary movement of a person’s eyeballs caused by drugs or alcohol. With the horizontal gaze nystagmus test, you have to follow a small object like for instance a penlight with your eyes and your head is still. The officer examines the motion of eyes moving the object back and forth while he is conducting this test. Officers are trained to identify three cues in each eye which can enable them to know whether a person is intoxicated or not. If they are able to get 4 out 6 cues then you can be arrested for DWI.

The cues are the following:

  • The inability of the person to follow the object
  • Involuntary jerking of eyeballs
  • The onset of the involuntary jerking prior to eye reaching 45 degrees from the center
One-leg Stand

Another test is the one-leg stand where you will be required to stand with your feet together while your arms are placed on the side. The officer instructs you to lift one foot, 6 inch. above the ground while your toe is pointed out. You will count out loud while doing this test. The officer must also require you not to use your arms or sway to get balance. There are 2 to 4 cues that the officer is looking for.

  • While you are trying to keep your balance, you may sway from side to side
  • To keep your balance, you lift your arms at least 6 inch.
  • You have a hard time maintaining balance.
Walk and Turn

The officer directs to stand on a line while your feet is in a heel to toe position while your arms are placed at the sides. Do not start unless he tells you to. You will have to take 9 heel to toe steps on that line while you are counting the steps aloud. Then, you turn and walk back. There are 4 to 8 impairment cues.

  • Inability to maintain balance during instructions
  • You begin walking even before the officer is done in giving instructions
  • You stop in the middle of the test
  • You fail to have the heel-to-toe touch by half an inch
  • You step off the line
  • You lose balance while walking or turning
  • You failed to follow the instructions
Sample of Non-Standardized Field Sobriety Tests

There are also other non-standardized tests that are used to determine a person’s cognitive and physical abilities.

  • Count backwards from 100
  • The Rhomberg stationary balance test
  • Recite the alphabet
  • Hand-pat test
  • Finger to nose test
Implied Consent

When you are arrested in New Jersey, you have to submit to a test to examine your blood alcohol concentration. This is commonly referred to as implied consent which means that if a law officer arrests you for drunk driving and you refuse to submit to a test, it might lead to a revocation of license.


In New Jersey, the Draeger Alcotest 7110 MKIII-C is administered. This test is used to determine the blood alcohol concentration. When an officer arrests you for DWI, the officer has to read the “Standard Statement” stating the penalties if you refuse.

Three conditions must be best for the admissibility of the test.

  • The device should be inspected and should work properly.
  • The person conducting the test should be certified.
  • The officer administering the test should follow the procedure.