Drennan Law Firm Drennan Law Firm Dui & Traffic Law Center
843-352-4149 Free Consultation
COVID-19 Notice: Drennan Law Firm is fully operational in accordance with safety regulations provided by the CDC and local health officials. Our attorneys continue to provide quality legal representation and are available to discuss your case over the phone, email, or Apple FaceTime.

What is the horizontal gaze nystagmus test?

Police officers in South Carolina and other states are increasingly targeting alleged drunk drivers that they deem "hardcore" -- those who have been through the DUI system on numerous occasions. Authorities argue that those particular defendants have already mastered the standardized field sobriety test so that they can perform it while intoxicated, which is why they advocate for the horizontal gaze nystagmus test. That evaluation, also known as the horizontal gaze test, evaluates a driver's sobriety by observing the behavior of his or her eyes while looking side-to-side.

There are issues, of course, with the horizontal gaze test. Attorneys and judges both agree that the gaze test is unlikely to be admissible in court, even though evidence suggests that it is more effective at identifying intoxicated drivers with BAC levels between 0.8 and 0.12 percent. Although this test has long been considered subjective and inadmissible in court, more prosecutors are pushing for its use and attempting to lay proper groundwork for its ongoing implementation.

When officers conduct the horizontal gaze test, they are looking for jumpy eye movement that occurs when the driver is attempting to follow a moving object such as a pen. The officer stands about an arm's length away to administer the test. Authorities argue that it is a particularly valuable tool because the defendant cannot achieve success against the test through practice -- our bodies cause the jumpy eye movements because of the effects of alcohol, no matter how we try to control the effect.

Even though authorities are pushing for increased admission of the horizontal gaze test in court, it is still considered subjective and therefore largely unreliable. Further, if a driver is not subject to a properly administered evaluation, an improper field sobriety test can be thrown out of court entirely, leaving little evidence for the prosecution. Even if you have failed a standardized field sobriety test or horizontal gaze nystagmus test, you are not automatically considered guilty of DUI; an attorney can help you understand your options.

Source: American Prosecutors Research Institute, "Admissibility of Horizontal Gaze Nystagmus Evidence," accessed Sep. 09, 2015

No Comments

Leave a comment
Comment Information

Call Drennan Law Firm — Free Initial Consultation

Speak with a Charleston criminal lawyer today who will work with you directly, one-on-one.
Please call us at 843-352-4149 or email us to schedule a meeting or for prompt legal assistance.

Email Us 24/7 For Fast Answers

Bold labels are required.

Contact Information

The use of the Internet or this form for communication with the firm or any individual member of the firm does not establish an attorney-client relationship. Confidential or time-sensitive information should not be sent through this form.


Privacy Policy

Main Office
1350 Chuck Dawley Blvd
Mt. Pleasant, SC 29464

Toll Free: 888-722-6179
Phone: 843-352-4149
Phone: 843-606-2970
Fax: 843-606-2971
Mt. Pleasant Law Office Map

Branch Office
Local: 843-352-4149
Toll Free: 888-722-6179