North Carolina DWI Tests

North Carolina HGN Test

When police officers suspect that a person has been driving while intoxicated, they sometimes ask the driver to step out of the vehicle and take a field sobriety test.While there are many tests conducted by officers, only three have been standardized by the National Highway Traffic Safety Administration (NHTSA). One of them is the Horizontal Gaze Nystagmus (HGN). If you were given this test, you should immediately contact DWI defense attorney Bill Powers of the Law Offices of Powers McCartan. This field sobriety test is not always 100% accurate.  There may be ways to refute the accuracy and proper administration of the HGN in court.

What is a nystagmus?

Nystagmus is a medical condition wherein your eyes jerk involuntary. Alcohol consumption can be a cause of nystagmus but millions of people actually suffer from a natural nystagmus, which is why this test is not without its flaws. Nystagmus can also occur when you look to one side as far as possible. That is especially true if the officer requires you to look to the corners for an extended period of time.  After a while your eye muscles can become tired. If improperly administered, the HGN test has little or no value in determining the existence of impairment.  The reason police officers use this as a field sobriety test is because alcohol can make nystagmus occur before your eyes reach a high peripheral angle and it can make nystagmus appear more pronounced. Again, the test must be performed carefully and consistent with proper test protocols. If rushed, the officer can easily cause rapid eye movements and otherwise misinterpret the results as a nystagmus due to impairment.

What happens during the HGN?

The police officer will have you follow a stimulus like a pen with your eyes (without moving your head). The object that you are following with your eyes must be at a comfortable distance for you to see it, which is normally around 12 inches from the bridge of your nose. If you have glasses you should be allowed to leave them on if you can’t see the stimulus without correcting your vision. When administering the test, the officer should make sure that as you’re taking the test your eyes won’t be distracted by moving traffic or by the lights on the officer’s vehicle. This can negatively affect your test results. If you have a glass eye, wear a patch or have vision in only one eye, the HGN test has little or no level of reliability. The officer can’t assume that both of your eyes will perform in the same way.

SFST Steps and Measurements

Horizontal Gaze Nystagums

  • Remove eyeglasses
  • Check pupils for equal size. If the two pupils are distinctly different in size it is possible the subject has a glass eye or some neurological disorder or head injury
  • Check eyes to insure they both track stimulus equally. If the eyes do not track together, the possibility of serious medical condition or injury may be present. NHTSA “Testing for HGN in a subject with an eye disorder or artificial eye has not been validated by research.”
  • Begin with Left Eye
  • Check each eye independently
  • Hold stimulus 12 to 15 inches in front of nose
  • Check for a “lack of smooth pursuit” – Center to side in two (2) seconds
  • Check both eyes twice to confirm observations
  • Check for “distinct nystagmus at maximum deviation” – Hold at Maximum Deviation for “minimum” four (4) seconds each time, nystagmus must be Distinct and Sustained.
  • Check both eyes twice to confirm observations
  • Check for “onset of nystagmus prior to 45 degrees” – The stimulus should be moved from 0 to 45 degrees at a pace taking four (4) seconds
  • Check both eyes twice to confirm observations

Vertical Gaze Nystagmus

  • Position Stimulus 12 – 15 inches from nose
  • Raise stimulus until the subject’s eyes are elevated as far as possible
  • Hold for approximately four (4) seconds

There are many defenses to the HGN test, so don’t plead guilty based on that alone.

North Carolina Walk and Turn Test

If you were recently arrested for DWI in North Carolina and police asked you to take the walk-and-turn test, or heel-to-toe test, immediately contact defense attorney Bill Powers of the Law Offices of Powers McCartan. DWI defense attorney Bill Powers has dedicated substantial time and resources to representing clients charged with DWI and may be able to refute the evidence of your field sobriety test results including the walk and turn.

Since alcohol is a known depressant that slows down your body’s central nervous system, police use field sobriety tests like the walk and turn to determine if you are driving while impaired or otherwise intoxicated. The walk-and-turn test is standardized by the National Highway Traffic Safety Administration because they believe it can be a reliable way for law enforcement officers to determine if a person is intoxicated. However, there are many things that can go wrong during the walk and turn that can affect your test results.

For starters, the police officer has to make sure you are an appropriate candidate for this test. People who are over 65 years old, overweight by more than 50 pounds or those who have physical handicaps should not to perform this test. If you can take this physical test, the officer should first demonstrate it for you so that you know what to do. He or she should also ensure that you perform the test on a flat, dry surface during reasonable weather conditions in a safe environment (away from traffic).

During the test, you will be asked to follow a line (either the white line on the shoulder of the road or an “imaginary” line if none exists). You are then supposed to walk nine steps heel to toe. Once you’ve counted out loud to the ninth step, you are requested to pivot and return in the same manner, heel to toe. You cannot use your arms for balance and if the officer notices you swaying, stumbling, missing a step or forgetting to count out loud, this can cause you to fail the test.

Walk and Turn (Sometimes called the “Heel to Toe” test)

  • Instruction stage – Left foot on line, right foot directly in front of left foot with heel touching toe
  • Do not move from this position until told to do so
  • Do you understand?
  • Walking Stage – When told to begin, take nine steps heel touching toe, when you reach your ninth step, leave your lead foot on the line and turn making a series of small steps, and then return nine steps heel to toe.  While you are doing this, keep your hands at your side, watch your feet at all times, count out loud and don’t stop until you have completed the test.
  • Do you understand these directions?
  • Must miss heel to toe by ½” or more
  • Must raise one or more hands 6” or more
  • There can be no more than 8 clues.  Each clue may be observed multiple times, yet still count only as one “clue”
  • NHTSA “original research indicated that individuals over 65 years of age had difficulty performing this test.”  Persons with back, leg or inner ear problems may have difficulty.
  • 2” or greater heels should be removed

Walk and Turn “Clues” or “Cues”

  1. Can’t balance during instructions
  2. Starts too soon
  3. Stops
  4. Misses heel to toe by ½” or more
  5. Steps off line
  6. Uses arms for balance
  7. Turns incorrectly
  8. Wrong number of steps

North Carolina One Leg Stand Test

Have you recently been charged with DWI in North Carolina? Did a police officer ask you to perform a field sobriety test known as the one-leg stand? If so, you should contact DWI defense attorney Bill Powers right away. Bill Powers of the Law Offices of Powers McCartan focuses his practice on the defense of DWI and can scrutinize the evidence of your one-leg stand test results. While this test is standardized by the National Highway Traffic and Safety Administration, there are many things that can go wrong during the test.

For example, did you know that police have certain protocols that they must follow when administering a field sobriety test? Prior to asking you to take the test, the officer must weigh certain factors such as: are you more than 50 pounds overweight, over 65 years old or physically handicapped? If so, you should not take this test. Also if you are wearing heels more than 2” high, you should be allowed to take them off before the test.

The officer must also make sure that you can perform the test in a safe environment, away from traffic. You cannot be expected to pass this test if you’re standing on a slippery surface, if you’re on a hill or if it’s windy. If it’s determined that you are a candidate that could be expected to reasonably perform this test, the officer must first explain and then demonstrate how to complete the test.

When you begin the test, the officer will first ask you to raise one of your legs (you have the right to choose which leg) six inches off the ground. You must keep your arms at your sides and cannot use them to help you balance. As you do this, the officer will ask you to count out loud to 30 by thousands:  one thousand one, one thousand two, one thousand three, and so forth all the way to thirty.

During the test, the officer will observe you to see if you use your arms to balance, hop, put your foot down more than twice, or sway while balancing. The officer will likely say that you failed to satisfactorily perform the test if he or she observed you exhibiting two of these clues or cues during the one-leg stand test.

One Leg Stand

  • Instruction Stage – Stand with feet together and arms at side, don’t move from this position until told to do so.
  • Do you understand?
  • Approximately 6 inches off the ground keeping foot point
  • Keep both legs straight, look at your elevated foot, count out loud One thousand and one, one thousand and two, and so on until told to stop
  • Officer must time for 30 seconds
  • Maximum of 4 clues for test

NHTSA certain individuals over 65 years of age, back, leg or inner ear problems, or people who are overweight by 50 or more pounds had difficulty performing this test. Individuals wearing heels more than 2” high should be given the opportunity to remove their shoes

One Leg Stand “Clues” or “Cues”

  1. Sway
  2. Arms to balance
  3. Hops
  4. Puts foot down