Field Sobriety Test

To confirm his suspicion that a driver is under the influence of alcohol, a police officer will typically request that the driver submit to field sobriety testing. This request will usually be delivered more like a command, but a person may refuse to submit to field sobriety testing. Field sobriety tests are “psycho physical” tests – “Psycho” as in mental, and “physical” as in coordination. The officer is looking to see whether a person can understand and remember instructions while performing feats of gymnastics.

The National Highway Transportation Safety Administration (NHTSA) has approved and validated three field sobriety tests:

  • The Horizontal Gaze Nystagmus Test: This is a test where the officer holds a pen or similar object in front of the subject’s eyes to determine whether she can follow it. The officer is also supposed to look for a “jerking” of the eye when the pen is held at a 45 degree angle. If this jerking is present it is supposed to indicate an alcohol concentration of over .10. While many police officers feel that this is the most reliable field test they have in their arsenal, it is not allowed in court unless the prosecutor has an expert witness to testify to its scientific validity. Thus, it is almost never introduced in court.
  • The One Leg Stand Test: This test requires that the subject stand on one leg with his hands down at his sides and count to 30. The officer will look for swaying, raising the hands for balance and the ability to count properly, among other things. This test is difficult for most people to do absent any alcohol whatsoever, and is especially difficult if a person has bad knees or ankles, a bad back, inner ear disorder, or any other physical limitation.
  • The Walk and Turn Test: This test is also called the heel-to-toe test and usually requires that a person walk nine steps heel-to-toe in a straight line, turn around, and walk nine steps back. The officer will look to see whether the subject stumbles, sways, uses his arms for balance, takes too many or too few steps, and how he executes the turn. Again, this test is hard for most people sober or not, and especially when taken on the side of a road with flashing police lights and traffic whizzing by.

All of the NHTSA approved tests must be administered exactly as prescribed in the NHTSA Manual or their validity is compromised.

Police officers usually have several other field sobriety tests that they administer, although they have not been scientifically proven to be reliable. These include the finger-to-nose test, requiring people to say the alphabet or count backward and forward, and touching their fingers together with their eyes closed. Our law firm has specific ways of dealing with each of these tests and usually files motions to limit their admissibility in the event of a trial.

It is extremely important that you inform your attorney of any physical and/or mental injuries, disabilities, or illnesses that you may have. Bad knees, ankles, hips or backs may explain away a lack of balance or coordination on field sobriety tests. People with learning disabilities like Attention Deficit Disorder may have trouble understanding and following an officer’s instructions. Allergies, inner ear disorders and sinus problems may also cause imbalance. This is the type of information upon which a successful defense is based.

Another test frequently used by law enforcement officers is the Preliminary Breath Test (PBT). This is a little machine that officers carry in their cars. Usually right before the officer makes a DUI arrest, he will have the driver blow into the PBT machine. The PBT will alert an officer as to whether there is alcohol on the driver’s breath, and some machines will indicate whether a person is over the limit or not. Police officers are supposed to wait fifteen minutes before administering this test but rarely do. This machine is very unreliable and, in fact, is not admissible in court to prove that a person was driving under the influence. It can only be used as evidence in court if the defendant (the driver) challenges the police officer’s decision to arrest him. Failure to take the PBT test is a traffic infraction for which a ticket may be issued and the driver fined (usually $50.00 to $200.00). However, it is a nonmoving violation and won’t go on a person’s driving record if convicted. The PBT and the breath test done later at the station are two different tests, on two different machines, and each has a different impact on your case.

If the officer finds that a driver did not perform these tests to his satisfaction, the driver will be arrested for DUI. At that point the driver is often handcuffed, searched for weapons and/or contraband, and placed in the officer’s car for transportation to the police station for booking and a blood or breath test. The officer is generally allowed to search the driver’s car to look for alcohol or drugs that may be involved with the DUI. The car is often towed at that point. Throughout this entire episode, from the point of initial contact until the driver is released, the officer will note the person’s attitude and behavior. Combativeness and belligerence are considered signs of intoxication. It always pays to be courteous and polite to a police officer.