The Horizontal Gaze Nystagmus Test: Is It Really Effective?

We’ve all probably been pulled over by a police officer at least once. That panic you feel, even if you know it’s simply because of a broken taillight, is reason enough to hope it never happens again. However, what if it wasn’t just a taillight or a speeding ticket but rather a few beers and a decision to drive home rather than take a taxi that led to you being stopped. Do you think you would pass the Horizontal Gaze Nystagmus sobriety test? Do you think you’d be able to drive away scot-free?

If this is the case, then you are sadly mistaken. In fact, only a small amount of individuals get away with drunk driving. Out of these individuals that carelessly drink and drive, 600,000 of them will be involved in an alcohol-related accident yearly. Although this is the case, many individuals have begun to speculate that the credibility of field sobriety tests is questionable and, in turn, tests such as the Horizontal Gaze Nystagmus, or HGN, test are jeopardized.

What is the Horizontal Gaze Nystagmus (HGN) Test?

The Horizontal Gaze Nystagmus (HGN) test is a test that measures the BAC of an individual and is based on a strange quirk in human biology. The average individual’s eye, when looking to the side, will involuntarily twitch after reaching an angle of 45 degrees. Whereas, an individual with a high BAC will twitch involuntarily before reaching the 45-degree angle.

By using this procedure, law enforcement is able to scientifically determine the BAC content of an individual. They can then do this without performing some of the more unsubstantial tests often performed. However, despite its scientific credibility, there are still many states that refuse its admittance in DUI cases and many other sources that refute its reliability based on the fact that it can be improperly administered and is based on the trust that these officers are being honest when performing the test.

How Commonly is The HGN Test Used?

Although HGN is quite commonly utilized in field sobriety testing, this may change in the next few years. This is due to the fact that multiple individuals questioning its credibility as a whole. In fact, in states such as South and North Carolina, Kansas, and Texas, although this test can be used as probable cause for a DUI-based arrest, it is not admitted in court cases regarding these arrests due to its inability to be recreated at any given time and the lack of proof regarding its use.

Although there are several questions about DUI charges that you must ask yourself, the credibility of this charge should not be one of them. In fact, many lawyers and judges state that there should be more consistent and effective tests implicated in the DUI court process. Despite the HGN test being one of the most effective ways to gain probable cause, many states are pushing for immediate breathalyzer testing instead.

Can The Horizontal Gaze Nystagmus Test Be Trusted?

In theory, the HGN test is the most effective field sobriety test thus far. However, its accuracy solely depends on the person in question’s physical attributes. ON top of this, the training which the officer has completed is vital likewise. If administered incorrectly, the test becomes null and void leading to its credibility in court becoming even more questionable.

However, if used alongside a breathalyzer, this could be ideal.  This form of testing may be a perfect way for officers to gain probable cause to administer a breathalyzer test. In doing so, this test would be valid proof that can be utilized in court. In turn, it could ensure that the individuals in question are fined or sent to jail for their actions.

The Future of Implicating The HGN Test and What May Replace It

The future of the HGN test may be in jeopardy. Although this test has been scientifically proven to be accurate, there are far too many variables included in its success. From the effects of common disorders on its accuracy such as Astigmatisms to the credibility of the officer’s administering– the future of the HGN test may lie in breathalyzers rather than its own use.

For instance, in many countries, the implementation of acts requiring citizens to carry their own breathalyzers have significantly decreased the DUI rates. America is not far behind. In some states, there are already laws being put in place that demand immediate breathalyzer testing for possible DUI charges. Although not a new topic, we may see the beginning of these new rules nationwide within this year.
At the end of the day, safety is the main issue. Whatever test is required to ensure that individuals are not drinking and driving is credible in some regard. For the HGN test, it may not be the most reliable way to determine the BAC of an individual. However, it certainly beats saying the alphabet backward when you’re dyslexic or walking in a straight line when you’re autistic. Because of this, the HGN test remains a credible source in the meantime. Therefore, knowing how it affects you can actually lead to a safer you and world as a whole.

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