Investigative Article: Uncovering the Truth about the Horizontal Gaze Nystagmus Test in DUI Field Sobriety

As we all know, drinking and driving is a serious offense that can cause injury, death, and legal consequences. As a result, police officers are hyper-vigilant when it comes to detecting and prosecuting drunk drivers. One of the most common methods used to assess a driver's level of intoxication is the Horizontal Gaze Nystagmus (HGN) test. However, as with any scientific test, there are limitations and errors that can occur. In this investigative article, we will examine the HGN test, how it works, and its limitations. We will also explore how attorneys like Arja Shah can help defend clients who have been charged with DUI based on the results of the HGN test.

What is the HGN Test?

The HGN test involves examining a suspect's eyes and observing their ability to follow a moving object horizontally while maintaining visual contact with the object. This test is based on the scientific principle that when a person is intoxicated, their eyes will jerk involuntarily when they try to follow an object. This involuntary jerking is called nystagmus. The HGN test is designed to detect and measure this nystagmus to determine if a person is intoxicated or not.

How Accurate is the HGN Test?

According to the National Highway Traffic Safety Administration (NHTSA), the HGN test is one of the most accurate field sobriety tests available to police officers. In laboratory conditions, the correct identification of intoxicated individuals was achieved in 88-90% of cases. In contrast, the Walk and Turn test was accurate in only 79% of cases and the One-Leg Stand test in only 83% of cases. However, it is important to note that the accuracy of the test depends on the proper administration by a trained police officer and the absence of confounding factors that may affect the results.

Limitations of the HGN Test

Although the HGN test is frequently used by police officers to detect impaired drivers, it is not without limitations that can lead to inaccurate results. There are several factors that can cause the nystagmus to occur, which are unrelated to intoxication. For instance, a person's age, medical conditions, or prescription drugs can all influence the results of the HGN test. Furthermore, the test must be conducted in an appropriate environment involving a properly lit area and a stationary and visible stimulus at an appropriate distance. Any deviation from the standard testing protocols can impact the accuracy and reliability of the test results.

Challenging the HGN Test Results

It is important to note that the results of the HGN test are not always accurate and can be challenged in court. Experienced DUI defense attorneys like Arja Shah are trained to identify possible flaws in the administration of the HGN test and use this information to defend their clients. They can argue that factors such as bright lights, traffic conditions, or medical issues influenced the results. Furthermore, attorneys can challenge the validity of the officers' certification and training in administering the test or raise doubt as to whether the test was conducted properly at all.

Conclusion

While the HGN test can be an effective tool for police officers to detect drunk drivers, its limitations must be recognized. As an investigative tool, the HGN test requires proper administration, interpretation, and consideration of confounding factors to maintain accuracy and reliability. Anyone facing a DUI charge based on HGN test results should consult with an experienced DUI defense attorney like Arja Shah to explore their available legal options.

HGN Test - Horizontal Gaze Nystagmus Test in DUI Field Sobriety