DUI Field Sobriety Tests and How to Challenge Them

When a police officer pulls over a person for suspicion of driving under the influence, one way they may try to determine if a driver is intoxicated is by requesting that the driver perform a set of field sobriety tests. Field sobriety tests require a person to complete a set of physical tasks while the police look for subjective signs that may indicate intoxication. There are several reasons why a person might fail a field sobriety test other than being under the influence of alcohol or drugs, and the experienced DUI defense firm of Disney Law is here to help. Call or text Robert Disney at 412-999-5765 or contact us today if you or someone you know has been arrested for driving under the influence in the Pittsburgh area.


Standardized Field Sobriety Tests


There are three standardized field sobriety tests approved by the National Highway Traffic Safety Administration (NHTSA). The first test is the horizontal gaze nystagmus test, otherwise known as the HGN test. The police officer observes the driver’s eyes while they follow a pen, flashlight, or other small object as it is moved from side to side. Horizontal gaze nystagmus is an involuntary movement of the eyes that naturally occurs when they are rotated at high angles, but for an impaired person the movement becomes exaggerated and occurs at lesser angles. During an HGN test, a police officer is looking for the following signs of impairment:


  • Inability of the driver to follow the moving object smoothly with their eyes
  • Distinct HGN jerking at maximum deviation
  • Onset of HGN jerking within 45 degrees of center


The second standardized test is the walk and turn test, otherwise known as the WAT test. This is a divided attention test, where the driver is asked to take nine steps, heel to toe, in a straight line, turn on one foot, and return in the same manner. A police officer will suspect intoxication if any of the following mistakes occur:


  • Inability to keep balance while listening to directions
  • Beginning the test before the instructions are finished
  • Stopping to regain balance
  • Failure to touch heel-to-toe
  • Stepping off the line
  • Using the arms for balance
  • Making an improper turn
  • Incorrect number of steps


The third standardized NHTSA test is the one leg standing test, otherwise known as the OLS test. This is also a divided attention test, where the driver stands with one foot six inches off the ground while counting aloud until the police officer requests that they stop. Police look for the following indicators of potential intoxication:


  • Swaying while balancing
  • Using arms to balance
  • Hopping to maintain balance
  • Putting down the foot


As you can see, the signs of potential intoxication that police officers look for with sobriety tests are incredibly subjective, and there are many reasons other than driving under the influence why a person might fail a standardized field sobriety test.


Non-Standardized Field Sobriety Tests


Police officers may also use a number of non-standardized field sobriety tests when they suspect a person of driving under the influence. These non-standardized tests are typically set by local and regional police practices and are often subjectively determined by whatever procedures or protocols that a particular police force established as passing or failing the test. Some of these tests include the following:


  • Finger-to-nose test
  • Recitation of the alphabet or a portion of it
  • Reverse counting
  • Finger-count test
  • Hand-pat test
  • Coin-pickup


To learn more about what types of tests the police might subject you to during a suspected DUI traffic stop, talk to an experienced DUI defense attorney today.


Refusing Field Sobriety Tests


It is incredibly important to know that you do not have to agree to field sobriety testing if you are pulled over by the police for suspicion of driving under the influence. Field sobriety tests are not part of the implied consent laws in Pennsylvania, as they are a far less reliable indicator of intoxication than a chemical test. A driver cannot be prosecuted for refusing to submit to field sobriety tests during a traffic stop.


Most police officers have already decided whether they believe a driver is intoxicated when they request that the person perform field sobriety tests, which makes the driver far more likely to fail. Once a sobriety test is failed, that gives the police the probable cause they need to arrest the driver for suspicion of driving under the influence. If you refuse to take the field sobriety tests, the police must use other, even less reliable evidence to try and determine intoxication, such as the smell of alcohol, alleged slurred speech, or the answers to any questions asked about where the driver has been that night.


Is Chemical Testing Different?


Chemical testing is different from field sobriety tests when a person is suspected of driving under the influence. Chemical tests, usually done through urine or blood, can only be performed after a person is officially arrested for suspicion of driving under the influence. These tests do fall under the Pennsylvania implied consent laws, which mean that if a person is behind the wheel they have given implied consent to perform a chemical test if arrested. However, they still have the right to refuse a chemical test, but there will likely be consequences for that refusal such as losing their driver’s license for a year. An experienced DUI defense attorney will be able to explain the difference between field sobriety and chemical testing as well as the potential consequences of submitting to or rejecting these tests with the police.


Talk to Our Office Now


It is important to remember that if you or a loved one is pulled over on suspicion of driving under the influence you do not have to agree to perform field sobriety tests for the police, and there are many reasons other than intoxication why a person might fail one of these subjective tests. Call or text Robert Disney at 412-999-5765 or contact us today at Disney Law to speak with a knowledgeable DUI defense attorney in Pittsburgh to discuss your case now.