top of page
Search
  • Writer's pictureBrian Foley

Montgomery County DWI Attorney - Field Sobriety Testing

Montgomery County DWI Attorney - Field Sobriety Testing - Brian Foley Board Certified in Criminal Law




The Three Standardized Field Sobriety Tests used in Montgomery County, Texas as explained by board certified criminal defense attorney Brian Foley.  Horizontal Gaze Nystagmus (HGN): The HGN test is designed to detect involuntary jerking of the eyes, known as nystagmus, which can be exacerbated by alcohol or certain drugs. During the test, the officer will observe the driver's eyes as they follow a moving object, such as a pen or flashlight, from side to side.


The officer looks for specific indicators of impairment, such as the inability to smoothly track the object or the onset of nystagmus at certain angles. Walk-and-Turn (WAT): The WAT test assesses a person's balance, coordination, and ability to follow instructions. The driver is instructed to take nine heel-to-toe steps along a straight line, turn around, and take nine steps back. The officer observes for signs of impairment, such as stepping off the line, using arms for balance, or failing to turn properly. One-Leg Stand (OLS): In the OLS test, the driver is asked to stand on one leg while keeping the other foot approximately six inches off the ground. They must count aloud by thousands (e.g., "one thousand one, one thousand two," etc.) until told to stop. The officer looks for indicators of impairment, such as swaying, hopping, or putting the foot down.


Developed by the National Highway Traffic Safety Administration (NHTSA), the 9-Step Walk and Turn test aims to evaluate a suspect's divided attention and balance. It operates on the premise that alcohol impairment impairs cognitive abilities and motor skills. Law enforcement officers undergo training to administer this test as part of the standard protocol for DWI investigations. Administering the 9-Step Walk and Turn Test During the 9-Step Walk and Turn test, the suspect is instructed to take nine heel-to-toe steps along a straight line, turn, and take nine heel-to-toe steps back. Specific instructions include keeping arms at the sides, maintaining balance, and counting each step aloud. The officer scrutinizes for indicators of impairment, such as: - Inability to maintain balance during instructions. - Initiating the test prematurely. - Pausing while walking. - Failure to touch heel-to-toe. - Stepping off the line. - Using arms for balance. - Incorrect number of steps. - Improper execution of the turn.


Interpreting the Test Results: The officer evaluates the suspect's performance based on criteria outlined by the NHTSA. Any deviations from the prescribed procedures or observable signs of impairment may be noted as evidence of intoxication. However, factors such as nervousness, fatigue, or medical conditions can influence test performance. Challenging the 9-Step Walk and Turn Test Despite its intended standardization, the reliability of the 9-Step Walk and Turn test can be contested. Defense attorneys may raise questions regarding the test's validity, considering factors such as the officer's training, environmental conditions, or the suspect's physical limitations. Additionally, video evidence of the test administration can offer crucial insights into the suspect's performance and any disparities in the officer's observations.

4 views0 comments

Comments


bottom of page