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Field Sobriety Tests

Monmouth County NJ DWI Defense Lawyers

A police officer must possess a reasonable basis to believe that an individual is driving while intoxicated and field sobriety tests are the biggest tool used to make this determination. The National Highway Traffic Safety Administration (“NHTSA”) has adopted  standardized tests for DWI detection which are to be used by law enforcement throughout the country, including Monmouth County. The two of the defense lawyers at Marshall & Bonus are among a small number (probably considerably less than 10 statewide) who are certified as instructors in this standardized field sobriety tests (“SFST”). You might ask why this would be important and the explanation is that our attorneys’ superior knowledge in proper administration and scoring of SFST allows us to dismantle not only the basis for an arrest but also proof of intoxication when scientific evidence of impairment (i.e. breath or blood test evidencing blood alcohol content) has been eliminated in a case. It also helps that the attorney who heads of our DWI Department, Colin Bonus, Esq., handles nothing but N.J.S.A. 39:4-50 cases. To speak to Colin or another lawyer at our firm, contact our office at 732-450-8300.

Standardized Field Sobriety Tests in New Jersey DWI Cases

There are three field tests that are considered the standard to be used in DWI detection including the: (1) Horizontal Gaze Nystagmus Test (“HGN”); (2) Walk and Turn Test (“WAT”); and (3) One Leg Stand Test (“OLS”). These tests are relatively self-explanatory with the exception of the HGN test. What this tool measures is the “nystagmus” or involuntary jerking of the eye as it tracks horizontally from side-to-side. The reason why this test is used is because the presence of alcohol in an individual’s blood stream causes nystagmus that worsens as the level of alcohol gets higher. The chart that follows outlines proper instructions, clues of intoxication, and the number of clues needed to fail each test.

Standardized Field Sobriety TestProper InstructionsClues Used To Score TestClues Needed to Fail Test
Horizontal Gaze Nystagmus Test1. Stand with your feet together, with your hands by your side.

1. Follow the stimulus with your eyes, but do not move your head. Focus on the stimulus until I tell you stop.
1. Lack of Smooth Pursuit of Left Eye.
2. Lack of Smooth Pursuit of Right Eye.
3. Distinct and sustained nystagmus at maximum deviation of left eye.
4. 3. Distinct and sustained nystagmus at maximum deviation of right eye.
5. Onset of nystagmus prior to 45 degrees of left eye.
6. Onset of nystagmus prior to 45 degrees of right eye.
7. Presence of vertical nystagmus.
4 Clues
Walk & Turn Test1. Put your left foot on the line, then place your right foot on the line ahead of your left, with the heel of your right foot against the toe of
your left foot.
2.Do not start until I tell you to do so.
2. Do you understand? (must receive affirmative response).
3. When I tell you to begin, take 9 heel-to-toe steps on the line
4. (demonstrate) and take 9 heel-to-toe steps back down the line.
5. When you turn on the ninth step, keep your front foot on the line and turn taking several small steps with the other foot (demonstrate) and
take 9 heel-to-toe steps back down the line.
6. Ensure you look at your feet, count each step out loud, keep your
arms at your side, ensure you touch heel-to-toe and do not stop until
you have completed the test.
7. Do you understand the instructions?
8. You may begin.
9. If the suspect does not understand some part of the instructions, only the part in which the suspect does not understand should be repeated.
1. Unable to keep balance during instructions.
2. Starts test too early.
3. Stops walking.
4. Does not maintain heel-to-toe.
5. Steps off line.
6. Uses arms for balance.
7. Improper turn.
8. Wrong number of steps.
2 Clues
One Leg Stand Test1. Stand with your feet together and your arms at your side. (demonstrate)
2. Maintain position until told otherwise.
2. When I tell you to, I want you to raise one leg, either one, approximately 6 inches off the ground, foot pointed out, both legs straight and look at the elevated foot. Count out loud in the following manner: 1001, 1002, 1003, 1004 and so on until told to stop.
3. Do you understand the instructions?
4. You may begin the test.
1. Sways while balancing.
2. Uses arms to balance.
3. Hopping during test.
4. Putting foot down.
2 Clues

DWI Attorneys With Unique Training To Counteract Field Sobriety Testing

When you consider that the average police officer has undergone only a few hours of training in field sobriety testing and writes less than two DWI offenses annually, proper roadside detection tends to be sloppy. The same is true when it comes to accurate testimony at the time of trial. Having a lawyer with far more extensive knowledge in this area than the typical police officer can be an invaluable tool for defending a DUI charge. Two of the attorneys at our firm, Colin Bonus and Jonathan Marshall, have days of training in proper administration and scoring of SFST. They have even been certified by the NHTSA as instructors in these tests. If you were arrested and charged with driving while intoxicated, an attorney at Marshall & Bonus clearly has the tools to dissect the allegations that you failed field tests. Call us at 732-450-8300 to speak to Mr. Bonus or another one of our lawyers immediately in a free consultation.