What is a Field Sobriety Test?

All too often, a hardworking man or woman chooses to unwind after a long work week by going out for a few drinks, only to be pulled over by law enforcement on their way home from a bar or club. The majority of people will call a taxi cab or ask a designated driver to give them a ride; anyone who does not may be stopped and randomly tested for sobriety. A person who fails a sobriety test may face several long-lasting consequences.

A law enforcement officer may order a vehicle to stop at a sobriety checkpoint or roadblock to investigate the driver for a variety of violations. An officer will often request a driver to pull over for questioning if he drives in a manner that indicates he may be driving while intoxicated. This includes behaviors like weaving in and out of designated driving lanes or crossing the center line in a road.

Types of Field Sobriety Tests

A police officer administers a field sobriety test to anyone whom he suspects of driving under the influence of alcohol. The following are the three most common field sobriety tests that were developed by the National Highway Traffic Safety Administration:

  • One-leg stand (OLS) test: A driver is required to stand in place with his arms down while he holds one foot a few inches off the ground. If he fails to do so, it may be an indication that he is intoxicated.
  • Walk-and-turn (WAT) test: A driver is asked to walk in a straight line while he places one foot directly in front of the other. By not retaining his balance, a suspect may be arrested for driving while intoxicated.
  • Horizontal gaze nystagmus (HGN) test: A police officer asks a driver to follow a moving object with his eyes. If the suspect’s eyes bounce, it may be an indication that his blood alcohol content (BAC) exceeds the legal limit that is established by the government. It is possible for a person’s eye impairments to cause a false positive on this test.

Challenging the Evidence From Field Sobriety Tests

A skilled criminal defense attorney understands the defects of field sobriety tests and can identify some common errors that may occur:

  • A police officer initiated an unlawful traffic stop.
  • There is no baseline for comparing results.
  • The officer’s way of conducting the field sobriety tests was flawed.
  • The test results were inaccurate because of factors like the driver’s age and weight.

If you would like to get more information about field sobriety tests or traffic stops, schedule a free consultation with attorney Mario Madrid by calling 713-877-9400.