Texas DWI Field Sobriety Tests

In order to prove probably cause for a DWI arrest in Texas, police may ask a person to perform field sobriety tests. The purpose of the tests are to show abnormal use of mental or physical faculties. The manuals for these field sobriety tests are given by the National Highway Traffic Safety Administration (NHTSA). The three tests are named the HGN, Walk and Turn, and One Leg Stand tests.

1) Horizontal Gaze Nystagmus (HGN) - The police officer will hold a pen-like object and instructs the person to follow the pen only with your eyes. The symptoms of being drunk are a lack of smooth pursuit, nystagmus (jerkiness of the eye), and nystagmus before 45 degrees.

2) Walk and Turn (WAT) - You will be requested to walk down an invisible line, stop, turn, and then walk back. Before performing this, the police officer will give you further instructions such as stanging in unnatural positions, and then told to begin walking the line. You are graded on ability to follow instructions, and ability to perform simple tasks.

3) One Leg Stand (OLS) - The officer will ask you to stand on one foot with the other foot lifted in front of you. As you are doing this, the officer will instruct you to lift your foot higher and higher for a period of 30 seconds, which causes you to lose balance.