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Standardized Test

Updated: Mar 5, 2023 @ 8:01 pm

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Understanding Standardized Sobriety Testing

Walk and Turn

During the walk and turn test a police officer will draw a line in the road about nine feet in length and asks the DWI suspect to walk heel-to-toe along the line until he reaches the end.

The suspect will then be asked to turn around and proceed back down the line walking heel-to-toe. Police officers are trained to look for DWI suspects that cannot keep their balance, stop during the test or leave space between heel-to-toe steps.

The One Leg Stand

The DWI suspect is asked to raise one leg roughly six inches off the ground and begin counting or reciting the alphabet out loud.

If the DWI suspect begins to raise his arms during the one left stand process or starts swaying, stumbling, trembling, or falling down it is usually a clear sign to the police officer that the suspect has likely been driving while intoxicated (DWI).

Horizontal Gaze Nystagmus

This is supposed to be the most reliable Standardized Field Sobriety Test. In this test the officer will move a small object in front of your face from side to side to see if the your eyes begin to involuntarily jerk or tremble.

Police officers are trained to pick up when a DWI suspect may be intoxicated because of involuntary eye spasms during this test.

There are many defenses to this test, including;

  • Prior head trauma
  • Naturally occurring Horizontal Gaze Nystagmus
  • Medical condition induced HGN
  • Objects passing in your periphery during testing
  • Officer improperly moves the object across your field of vision
  • Officer held the object too close, or too far from your nose
  • Officer failed to move the object in a horizontal line
  • Medicine induced nystagmus
  • Other nystagmus present that the officer mistook for HGN
  • Officer performed the test too quickly, or too slowly
  • Officer gave you improper or incomplete instructions

Charged with DWI/DUI? Call Attorney Tad Nelson

Houston DWI Attorney Tad NelsonAttorney Tad Nelson is your local expert for all matters related to fighting prosecution of DWI offenses in Harris County, TX and Galveston County, TX. There are a number of cases that we’re able to win for our clients without even stepping into a courtroom.

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Understanding Standardized Sobriety Testing

The Law Offices of Tad Nelson & Associates

Houston DWI Lawyer Tad A Nelson is Board Certified in Criminal Law by the TBLS.

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