Bay Area DUI Lawyer DMV Hearing and License Suspension

• Introduction
• DUI Stops
• Sobriety Checkpoints
• Probable Cause
• Legal Requirements
• Legal Challenges
• Field Sobriety Tests
  • Standardized FST
    • Horizontal Gaze Nystagmus
    • Walk and Turn Test
    • One-Leg Stand Test
  • Non-Standardized FST
• Chemical Testing
• Accident Investigation
• Accident Reconstruction

One-Leg Stand Test

California police officers, California the Highway Patrol (CHP), or sheriff's deputies who suspect a driver of driving under the influence (DUI), or driving while intoxicated (DWI) require to perform a Field Sobriety Test (FST) to gather evidence to support the DUI charge. The One-Leg Stand test is one of three standardized field sobriety tests recognized by the National Highway Transportation Safety Administration (NHTSA).

Unfortunately, police officers don't use the One-Leg Stand test to determine whether a driver is impaired - they are used to justify the arrest and gather evidence for the criminal court case and the California DMV. A California criminal defense attorney knowledgeable in DUI defense can effectively challenge the results of field sobriety tests such as the One-Leg Stand test as part of an aggressive drunk driving defense.

Like other field sobriety tests, the One-Leg Stand exercise is a divided-attention test - it is designed to evaluate mental and physical impairment by forcing a driver to concentrate on two tasks at once. Prosecutors will use the results of One-Leg Stand test to argue that any difference between the way the officer explained and demonstrated the tests, and the way the driver performed the tests, is evidence of mental or physical impairment.

When administering the one-leg stand test, police officer directs the driver to stand with arms down and feet together during the test. The officer then instructs the driver to raise one leg off the ground, keeping the foot parallel to the roadway. The driver is told look at his/ her foot while counting "one thousand one, one thousand two, one thousand three" until told to stop, typically for 30 seconds.

Police look for four signs of impairment - hopping on one foot, swaying while balancing, using the arms to balance, and putting his or her foot down three or more time during the test. If police officer spots two or more of these signs, he or she will assume that the driver has a blood alcohol content (BAC) of .10 or greater, and the motorist will be arrested for driving under the influence.

However, the one-leg stand and many other field sobriety tests are inherently unfair, because they measure physical impairment as a sign of intoxication. To understand why this is unfair, it's helpful to understand how alcohol affects the human body. Experts agree that alcohol intoxication always causes mental impairment before physical impairment takes place. If no mental impairment exists, then any physical impairment must be attributed to factors other than alcohol.

In order to prove driving under the influence (DUI), or driving while intoxicated (DWI) charge, the prosecutor must present evidence of both mental and physical impairment. The physical impairment displayed in the One-Leg Stand test can be attributed to sources other than alcohol, such as injury or illness. A California criminal defense lawyer who focuses on drunk driving defense can prove that there are many reasons other than alcohol impairment why a driver may perform poorly on the one-leg stand test.

People who haven't had a single drink may have difficulty standing on one leg for 30 seconds. The one-leg stand test can be particularly challenging for drivers with back or leg injuries, individuals with inner-ear disorders or other balance problems, drivers over 65, and those who are overweight. Uneven ground or heels higher than two inches can add to the challenge.

It is important to keep in mind that the results of a field sobriety tests such as the one-leg stand test are open to interpretation. The experienced San Francisco Bay Area DUI attorneys at the Law Office of Robert Tayac know that many signs of impairment noted in the One-Leg Stand test can be caused by factors other than alcohol, and prove that a driver's performance in the one-leg stand test could just as easily show that the driver was not impaired.

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