When police officers in Maryland suspect a driver of being impaired, they usually administer field sobriety tests. These tests are used by officers to help determine probable cause to make an arrest. The Standard Field Sobriety Test (SFST) used by officers around the country is comprised of three different tests.
Horizontal gaze nystagmus
In the horizontal gaze nystagmus (HGN) test, the driver is asked by an officer to follow a moving object, usually a flashlight or pen, slowly from side to side. When a person’s eyes are rotated at high peripheral angles, an involuntary twitching occurs, known as horizontal gaze nystagmus. This twitching of the eyes is more exaggerated when an individual is intoxicated.
The one-leg stand test is used to gauge a driver’s balance. The driver is asked by the officer to stand on one leg with the other foot about six inches off the ground. The officer will ask the driver to count from 1001, 1002, and so on until the officer ends the test.
For the walk-and-turn test, the driver is asked to take nine heel-to-toe steps along a straight line. The driver then turns 180 degrees on one foot and returns with nine steps in the opposite direction. The officer looks for several factors during this test that could indicate the driver is intoxicated.
What to do if charged with DUI
It is important to know that these field sobriety tests are not always accurate. Many factors can skew the results. Regardless, if a driver fails any of these tests, an arrest for DUI may follow. Those in Maryland who have been charged with a DUI have the right to consult with an experienced criminal defense attorney to protect their legal rights and pursue a favorable result in court.