Horizontal Gaze Nystagmus Test

The Horizontal Gaze Nystagmus (HGN) test is a field sobriety test used by law enforcement to determine whether or not a suspected driver is under the influence of alcohol. The test involves an officer asking a driver to follow some stimulus, usually a pen, with their eyes to the left and right. The officer will then determine when the eye begins involuntarily jerking, or exhibiting nystagmus. While all eyes experience this involuntary twitch when looking at a significant angle, those with higher blood alcohol levels begin twitching sooner. According to the National Highway Transportation Safety Administration, HGN tests are 77% reliable in determining whether or not a driver’s BAC is above .10%.

How does an officer determine nystagmus?

A HGN test cannot confirm or deny the amount of alcohol that a suspected driver may have in their system, but indicates to the police officer that there may be some level of impairment present.

When testing HGN, an officer will check for the following questions:

1. Are the eyes moving smoothly from one side to the other or noticeably jerking?
2. Are the eyes jerking when they have moved as far as possible to one side?
3. Does the eye begin jerking before it has reached a 45-degree angle?

There are a few factors that can affect the outcome of an HGN test. A suspect that is wearing eyeglasses may make it more difficult for the officer to see the angle at which the suspect’s eyes begin to twitch. Additionally, if the HGN test is not administered in a well-lit area, the officer may not be able to tell when nystagmus occurs. Suspects should not be facing headlights or the lights of a police vehicle since this can cause nystagmus without the help of alcohol. If any of these apply in a suspected driver’s case, the results of the HGN test may be inadmissible in court. 

There are other defenses to HGN tests, including the ability of the officer to determine a 45-degree angle, the presence of prescription drugs in the body of the accused, the presence of a head injury, and more. Working with a DUI defense attorney will be the best bet in clarifying the cause of nystagmus and whether the results of this test can be permitted in court. 

Jonathan Blecher Appears on Radio Talk Show

I had the pleasure of being invited to appear as a guest on a local radio program, Fried on Business, which is heard every Thursday from 5-6 PM on 880AM-The Biz, Miami's Bloomberg Radio affiliate. I appear on Jim Fried's program as a legal consultant on criminal law issues, particularly DUI and the business surrounding it.

This episode revolved around DUI and the holiday season. Jim and I discussed what rights people have during a DUI traffic stop, DUI sobriety checkpoints and whether roadside sobriety exercises are mandatory, or even fair. We also talked about breath, blood and urine testing and driver license suspensions that stem from a DUI arrest.

Jim's viewer's wanted to know what the penalties are for a DUI conviction in Florida and we went into some detail on that topic. We discussed how there are potential, long-term, negative collateral consequences that could flow from a DUI conviction including strangled employment opportunities, increased insurance rates and even immigration concerns. Did you know that Canada will turn you away at the border if they discover a U.S. DUI conviction on your record, unless you undergo a 5-year rehabilitation period?

We also discussed the concerns over distracted driving, which poses an even greater safety risk than DUI. A study by Car and Driver magazine concluded that reaction time and stopping distance was more severely affected by texting and reading e-mail than it was by driving with a blood alcohol of .08.

Listen to the interview by clicking here.

All You Need To Know About Roadside Sobriety Exercises

Undergoing Sobriety Examinations

It's going to be a shock when you're driving home from the bar or a party and all of a sudden you see the flashing lights of a police car in your rear view mirror. If you know you've had one too many drinks that night, your first feelings are usually of panic, fear, and regret. But if you feel as if you've done nothing wrong, regardless whether you've had something to drink or not, then you're more confused than anything else.

In most cases when the police officer pulls you over and asks you to step out of your vehicle, there's a good chance that you may be asked to perform some exercises to dispel the officer's suspicions that you may be driving under the influence of drugs or alcohol. These tests are called Field Sobriety Exercises.

What does a Field Sobriety Exercise entail?

Standardized field sobriety exercises are at the police officer's discretion and are usually administered if they feel that there's enough physical observation evidence to suspect a DUI.

In my opinion, these tests were designed with an unfair advantage over the subject; ultimately resulting in failure in one or several areas. There are many factors aside from being intoxicated that can lead to a failed sobriety test. 

Here are a few things that can negatively affect your outcomes.

• Over-the-counter medication that can make you sleepy or groggy
• A drink or two, though under the drinking limit, can still impair your ability to pass the test to some degree
• Naturally lacking coordination and balance
• Physical disabilities, injuries experienced in the past or limited mobility of limbs
• Poor roadside conditions
• Over 60 years of age
• More than 50 pounds overweight

There are many parts to a sobriety test which can include both standardized and non-standardized testing. The entire process can last for several minutes depending on how many of the following you're asked to do.

National Highway Traffic Safety Administration standardized tests are:

• One-leg stand
• Walk-an-turn
• Horizontal Gaze Nystagmus (HGN)

Other tests may include the following non-standardized tests:

• Finger-to-nose
• Finger-count
• Reciting the alphabet (forward or backwards)
• Number counting (forward or backwards)
• Rhomberg Balance

While the tests are being administered, the police officer will be closely observing and scrutinizing your every move; looking for wobbling, swaying, falling, stumbling, flailing of the arms, slurred speech and other signs of intoxication.

What happens after you refuse a sobriety exercise?

A lot of people are under the impression that a field sobriety test is a requirement if and when a police officer asks you to perform them, but in fact it's not. If you ask an officer if the sobriety tests are "voluntarily" then an overwhelming percentage of them will have to say yes, giving you the right to politely refuse to take them. In that event, unlike breath, blood or urine tests, refusing to do a sobriety exercise will result in no penalties and will not be used against you in court.

Have Questions? Call An Experienced DUI Lawyer.

Have more questions about your DUI case? Call Attorney Jonathan Blecher, P.A. to discuss your situation during a free case evaluation. Attorney Blecher has been defending DUI cases in Miami for over three decades and has the knowledge you need on your side.