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Field Sobriety Tests

Field Sobriety Tests

Law enforcement uses a series of physical exercises called field sobriety tests to determine if a person is impaired by drugs or alcohol. Police officers have drivers perform field sobriety tests such as walking heel-to-toe on a line when they are pulled over for driving while intoxicated. Field sobriety tests can seem silly, but they can be used as evidence against you in trial.

DWI testing is never flawless, especially field sobriety tests. It’s very possible for a sober person to fail one or more field sobriety tests. External factors such as physical ability, weather, and even traffic can skew your results. In some cases, it’s the best option to refuse testing altogether.

If you or someone you know has been charged with a DWI, it’s vital that you seek trusted legal representation. 

Attorney for Field Sobriety Tests in Harris County, TX

Refusing field sobriety tests during a DWI stop can be beneficial. Police officers may want you to complete physical exercises that aren’t possible due to physical ability, age, disability, or other factors. Even simple circumstances during testing such as slippery road may lead to misleading results. 

Attorney Matthew Horak is practiced in Texas criminal courts. Horak Law has handled numerous DWI cases, including ones where clients refused any sort of DWI testing. Matthew Horak has the experience and drive necessary to make a strong defense for you. Call now at (713) 225-8000 and schedule a free consultation today.

Horak Law practices law throughout the greater Houston metropolitan area and surrounding communities including Greenspoint, Gulfton, Brays Oaks, and River Oaks. 

Overview of Field Sobriety Tests in Texas

Standardized Field Sobriety Tests in Harris County, Texas

You may see a variety of field sobriety testing on television or over the Internet. However, only a few tests have been standardized by the National Highway Traffic Safety Administration (NHTSA). These tests are incredibly valuable to the prosecution and can be used against you in court. 

The following are the three field sobriety tests that have been standardized by the NHTSA.

  • Horizontal Gaze Nystagmus (HGN) – When a person is intoxicated by drugs or alcohol, their eye may do an involuntary jerking known as nystagmus. A horizontal gaze nystagmus (HGN) test measures your nystagmus to determine if you’re impaired by drugs or alcohol. The police officer will hold an object 12 to 15 inches from the driver’s eyess and slowly move it from side to side. The driver will be asked to follow the object with their eyes and if they’re having issues tracking the object it’s a sign of impairment. According to the NHSTA, HGN tests have a 78 percent accuracy. However, this isn’t always the case. Simple outside stimuli have been known to skew HGN tests results such as heavy traffic, loud horns, or inclement weather.
  • One-Leg Stand (OLS) – A very common field sobriety test is the one-leg stand. For this test a police officer will ask the driver to stand on one foot about six inches off the ground. Usually, the driver instructed to count aloud for 30 seconds in the thousands. If the driver has issues with balance, hopping, or cannot perform the test police officers may infer the driver is intoxicated. Some factors can cause false results for an OLS test such as fatigue, age, or physical ability.
  • Walk-and-Turn (WAT) – Law enforcement may have you do a walk-and-turn test to determine if your physical faculties are impaired or not. The police officer will ask the driver to take nine heel-to-toe steps along a straight line. After they’ve reached the end, the driver must turn on one foot and take another nine head-to-toe steps back. A perfectly sober person can fail WAT tests due to certain factors. Some of these can include slippery roads, impaired vision, or terrible lighting at the stop.

Non-Standardized DWI Field Sobriety Tests in Houston, Texas

Most officers utilize the field sobriety tests standardized by the NTSA. However, some officers use additional testing to measure a driver’s level of impairment. None of these tests have been standardized by the NHTSA and may not be deemed admissible in court. Nonetheless, many law enforcement officers use them to determine a driver’s state. 

Below are some field sobriety tests used by Texas law enforcement: 

  • Romberg Balance Test – The Romberg Balance Test is frequently used by law enforcement to measure impairment. A police officer will ask the driver to stand with their feet together, head tilted back, and eyes closed. Then the officer will ask the driver to call out “stop” once the driver believes 30 seconds have passed. For this test, law enforcement is looking for signs of intoxication such as swaying, body tremors, and inability to stand straight for signs of intoxication.
  • Numbers Backward Test – Police officers may ask the driver to perform mental tests instead of physical ones. A common one is the numbers backward test. A police officer will ask the driver to count backward for a certain number. During the test, law enforcement will look for any signs of speech errors, confusion, slurred speech, and other signs of impairment.
  • ABC Test – A common field sobriety test is to recite or write the alphabet. Sometimes a police officer may even ask you say the alphabet backwards. For this test, law enforcement is looking for signs of struggle such as missed letters, slurred speech, and if their breath smells like alcohol.
  • Finger-to-Nose Test – A finger-to-nose test measures your self-awareness. Law enforcement will ask you to close your eyes, tilt your head back, and touch your nose with your index finger. The officer will ask you to perform the test three times with each hand. Typically, officers will look for signs of impairment such as stumbling, swaying, or inability to finish the test.

Can You Refuse a Field Sobriety Test in Texas?

Texas implied consent laws only incorporate chemical testing using breath, blood, or urine samples. Field sobriety testing isn’t included, and you’re allowed to refuse testing at any time. Even if you are in the middle of one test you can still refuse to comply with further field sobriety testing. Ultimately, the choice is up to you. Each option can bring about different results and carries their own pros and cons.

If you’re completely sober and physically fit it may be the best idea to submit to testing. Many people complete field sobriety tests without any problems. Unfortunately, this isn’t always a guarantee. Perfectly sober people have failed field sobriety testing before due to external factors such as age or weather.

Although field sobriety testing isn’t incorporated in implied consent laws, you can still be arrested. If law enforcement has probable cause that you’re intoxicated, they can still arrest you. The arrest and booking process can be incredibly overwhelming. Nonetheless, it may be the best idea for your situation. You may be in jail for a short period of time, but the prosecution will not be able to use any testing evidence. It may be the best course of action to endure detainment for a night or so then to handle the statutory penalties for a DWI.

Factors that Affect Field Sobriety Testing in Harris County, Texas

Field sobriety tests are by no means faultless and have had skewed results in the past. Law enforcement may not consider the external factors that can significantly alter the results of the tests. Also, simple reactions to a DWI stop such as nervousness may give a police officer enough reason to believe you’re intoxicated.

Some factors that can cause a completely sober person to fail a field sobriety test include, but are not limited to:

  • Fatigue;
  • Age;
  • Prior injuries;
  • Certain medical conditions;
  • Slippery roads;
  • Sleep medication;
  • Allergy medication such as Benadryl;
  • Physical disabilities;
  • Eye-to-hand coordination;
  • Improperly given instructions;
  • Inclement weather during the stop;
  • Certain shoes such as flip-flops;
  • The temperature outside;
  • Bad balance;
  • Extreme nerves and anxiety;
  • The lighting around the stop; and
  • Physical ability. 

Additional Resources

Texas SFST Training Program – Visit the official website for the Texas Standardized Field Sobriety Testing (SFST) Training Program. Find more information about upcoming SFST classes, who the SFST instructors are, and resources for officers looking to complete SFST training.

Drunk Driving – Visit the official website for the National Highway Traffic Safety Administration also known as NHTSA. The administration is in charge of standardizing and testing field sobriety testing for law enforcement. Access the site to learn about drunk driver statistics, alcohol’s long and short-term effects, and additional resources on DWI.

Lawyer for Field Sobriety Testing in Houston, Texas

If you or someone you know has refused field sobriety testing for a DWI, it’s important that you seek trusted legal representation. You could face criminal charges with serious penalties such as large fines and possible jail or prison time. Stay ahead with Horak Law and start planning your defense today. 

Attorney Matthew Horak is familiar with DWI testing strategies used by law enforcement. Not only has Matthew Horak had experience with many DWI cases, but he has a passion for defending his clients. Find an attorney who’s compassionate with clients but aggressive in the courtroom with Matthew Horak.

Contact attorney Matthew Horak at (713) 225-8000 today to schedule a free consultation. We accept clients throughout the greater Harris County area and surrounding counties including Fort Bend County, Liberty County, Brazoria County, and Galveston County.

This article was last updated on November 27, 2018.



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