Field Sobriety Tests

During a DWI stop, it’s common for law enforcement to ask the driver to submit to field sobriety testing. Field sobriety tests are a set of physical activities drawn out by law enforcement to determine whether a person is sober or not. Often, police will ask individuals to perform these test before conducting any chemical testing. 

Field sobriety testing isn’t by any means flawless. In fact, a perfectly sober person can fail a field sobriety test. Certain factors like age, weight, and old injuries can affect your ability to successfully complete field sobriety tests. It may be the best option to refuse field sobriety testing altogether if you’ve been pulled over for a DWI. 

Brownsville Attorney for Field Sobriety Tests in Texas

In some cases, it’s beneficial to refuse to participate in any field sobriety tests. A police officer may ask you to do tasks outside of your physical ability or the dashcam may capture misleading footage where you appear drunk. If you or someone you know has been arrested for refusing DWI testing, it’s vital that you seek trusted legal representation. 

Johnathan Gracia is an experienced criminal defense attorney who is dedicated to his clients. He has defended numerous people from DWI allegations throughout the Cameron County area. Through his defense techniques, collection of compelling evidence, and knowledge he can create a strong case for your charges. 

Call Johnathan Gracia at [$phone]] now for a free consultation. The Gracia Law Firm represents those accused of a DWI throughout the greater Brownsville area including Harlingen, La Feria, Rio Hondo, and Palm Valley.

Overview of Field Sobriety Tests in Texas


Types of Standardized DWI Field Sobriety Tests in Texas

The National Highway Traffic Safety Administration (NHTSA) has developed three field sobriety tests for United States law enforcement. These Standardized Field Sobriety Tests (SFSTs) are the most valuable to the prosecution since they have written rules and regulations. However, police officers are known to use tests outside of SFSTs when determining a person’s impairment level.

The following are the three SFSTs provided by the NHTSA. 

Horizontal Gaze Nystagmus (HGN)

An HGN test is considered to be the most accurate out of all the field sobriety tests. It measures the involuntary jerking of the eye when an individual is impaired by drugs or alcohol, which is referred to as nystagmus. An officer will hold a “stimulus” such as a pen about 12 to 15 inches away from the driver’s nose. Next the officer will slowly move the stimulus side to side and ask the driver to follow it with their eyes. 

The driver is instructed not to move their head while the object is moving. During the test, police officers will look for any signs of nystagmus. Some common signs they search for are lack of a smooth pursuit when eye tracking the object or nystagmus signs at a 45-degree angle. Although these tests are the most accurate, simple outside stimuli can easily disrupt the test.

One-Leg Stand (OLS)

A common field sobriety tests is a one-leg stand. Law enforcement will ask the driver to stand on one foot about six inches off the ground. They are then instructed to count aloud by the thousands for 30 seconds. The test will measure the following to search for signs of intoxication:

  • Hopping;
  • Excess swaying to balance;
  • Cycling arms for balance;
  • Tapping foot on the ground; or
  • Inability to keep balance at all.

Many factors can affect a one-leg stand test. Common issues can incldue balance, fatigue, and age. 

Walk-and-Turn (WAT)

A walk-and-turn test is exactly how it sounds. A police officer giving the test will instruct the driver to take nine heel-to-toe steps along a straight line. Once the driver has reached the end of the line, he or she is to turn on one foot and return back to the start in nine heel-to-toe steps. The officer will assess the driver and try to spot any of the following:

  • Inability to stay balanced;
  • Excessive stops while walking;
  • Inability to touch heel-to-toe;
  • Toes off the line;
  • Falls during the exercise;
  • Loses balance while turning;
  • Turning incorrectly; or
  • Inability to perform the test at all. 

WAT tests can easily be failed if a person has a handicap, bad coordination, or the lighting around the stop is bad.


Non-Standardized DWI Field Sobriety Tests in Cameron County, Texas

Although officers are taught to do the tests provided by the NHTSA, they might add or perform different tests based on their jurisdiction. These tests are not standardized by the NHTSA and may not be considered admissible by prosecutors. However, law enforcement still utilizes these tests if they see fit.

Some non-standardized field sobriety tests used by Texas law enforcement include:

  • ABC Test – Officers may ask you to recite or write a portion of the alphabet or the entire alphabet. In some cases, they may even ask for the alphabet backwards. Police officers will then try to detect any slurred speech or errors during the test.
  • Romberg Balance Test – A common test used by law enforcement is the Romberg Balance test. Law enforcement will ask you to stand with your feet together, head tilted back, and eyes closed. Next the officer will ask you to say the word “stop” once you believe 30 seconds have passed. The officer will look for any swaying, body tremors, or external signs of impairment during a Romberg Balance test.
  • Finger-to-Nose Test – Another test frequently used by law enforcement is the finger-to-nose test. You will be asked to close your eyes, tilt your head back, and touch your nose with your index finger. Each hand will perform the test three times. Officers will look for any physical signs of intoxication.
  • Numbers Backward Test – Similar to how it sounds, this test will require you to county backwards from a certain number. Police officers are required to analyze for any slurred speech, errors, or signs of impairment. 

Factors that Affect DWI Sobriety Testing

DWI sobriety testing is considered a developing field. While law enforcement utilizes these tests, external factors can seriously affect the results of the tests. The tests don’t take into consideration factors such as age, disabilities, or situational factors. The following are some factors that can cause a completely sober person to fail a field sobriety test.

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

Can I Refuse Field Sobriety Tests in Texas?

Implied consent laws don’t include field sobriety testing. You can refuse testing at any time during a DWI stop. Meaning you can complete one test and then refuse to submit to any others. The choice is ultimately up to you, and there are pros and cons to either choice. 

If you are sober and physically confident, it might be the best option to go through with testing. However, it’s important to note that people have failed field sobriety tests completely sober. Understand that if you refuse field sobriety tests, you can still be arrested for a DWI. If a police officer has probable cause that you are impaired, he or she can still arrest and book you. 

An arrest can be extremely stressful, but in some situations it’s the best option. You may be arrested for a short period of time, but prosecutors will not have any test evidence against you. Instead they will only have subjective evidence supplied by your arresting officer. In some cases, it’s best to be detained for a night or so then to carry a DWI conviction on your record. 


Additional Resources 

Instructor Guide to SFST Testing – Visit the Instructor Guide to Field Sobriety Testing by the National Highway Traffic Safety Administration. Find more detailed information surrounding the NHTSA’s tests, what police officers are trained to look for, and how police officers’ approach certain DWI scenarios. 

Drunk Driving – Visit the official website for the National Highway Traffic Safety Administration and find more information on drunk driving. Learn data and statistics surrounding drunk driving, how alcohol affects a person’s motor functions, and additional resources on DWIs. 


DWI Lawyer for Field Sobriety Testing in Cameron County, Texas

If you or someone you know has been charged with a DWI due to refusal, it’s important that you seek a practiced criminal defense attorney. Johnathan Gracia is a seasoned attorney who has represented numerous clients who refused field sobriety testing. 

Attorney Johnathan Gracia has a strong focus in criminal defense. He is very familiar with law enforcement tactics for DWIs and their possible inaccuracies. Johnathan Gracia can use his experience, knowledge, and defense strategies to formulate a strong case for you.

represents those accused of crimes throughout the greater Cameron County area and adjoining counties including Hidalgo County and Willacy County.


This article was last updated on November 5, 2018.

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