DFW Metroplex


Field Sobriety Tests in Fort Worth DWI Cases: Understanding Your Rights

Field sobriety tests are a common tool used by law enforcement officers to assess a driver's sobriety when they suspect a case of Driving While Intoxicated (DWI) in Fort Worth, Texas. This article will explore three specific field sobriety tests: the Walk & Turn Test, the Horizontal Gaze Nystagmus (HGN) Test, and the One-Leg Stand Test. Understanding your rights and the potential inaccuracies associated with these tests in DWI cases is crucial.  

The Walk & Turn Test

Purpose of the Test:

  • The Walk & Turn Test evaluates a person's ability to divide their attention effectively, a skill required for safe driving.

  • Test Procedure:

    • The individual is instructed to stand heel-to-toe with arms at their sides, an uncomfortable position for most.

    • While maintaining this stance, the officer provides instructions for taking nine heel-to-toe steps in a straight line, turning, and returning similarly.

    • Law enforcement looks for signs such as balance issues, starting too soon, or deviating from the imaginary line.

  • Challenging the Test:

    • DWI attorneys often challenge the accuracy of this test, as it may not reflect a person's true ability to operate a vehicle safely.

The Horizontal Gaze Nystagmus (HGN) Test

Purpose of the Test:

  • The HGN Test is designed to identify involuntary eye jerking, or nystagmus, triggered by alcohol or certain medications.

  • Test Procedure:

    • The accused person is asked to follow a stimulus with their eyes.

    • The law enforcement officer observes the point at which nystagmus begins, usually before or at a 45-degree angle, which can indicate intoxication.

  • Potential Inaccuracies:

    • While it is claimed to be 77% accurate, the HGN Test can produce false-positive results.

    • Factors like incorrect angle estimation, contact lenses, or flashing lights may lead to inaccurate conclusions.

The One-Leg Stand Test

Purpose of the Test:

  • Like the Walk & walk-and-turn test, the One-Leg Stand Test evaluates a person's multitasking ability.

  • Test Procedure:

    • The individual must balance on one leg with the other raised about six inches off the ground and toes extended.

    • While maintaining this posture, they must count aloud from 1 to 20.

  • Challenging the Test:

    • Some individuals naturally struggle with balance on one leg, irrespective of alcohol consumption.

    • DWI attorneys can challenge the results of this test by highlighting these factors.


Understanding your rights and the potential inaccuracies associated with field sobriety tests is crucial if you are arrested for DWI in Fort Worth, Texas. Seeking legal counsel from experienced DWI attorneys like those at Jones Miyazono, Fort Worth Criminal Defense Lawyers, can help you navigate the legal complexities and build a strong defense against DWI accusations. Contact a Fort Worth DWI lawyer for a free consultation to ensure your rights are protected, and your case is handled with expertise.

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