Drivers who are pulled over on suspicion of drunk driving might be asked to take a standardized field sobriety test before a police officer decides to make an arrest. This is a series of physical and cognitive tasks designed to give the officer an indication of whether the driver is impaired.
Many drivers don’t realize that how they perform on these tests could play a significant role in whether they’re arrested and what happens with their case.
The three tests in a standardized field sobriety test
There’s more than one type of field sobriety test, but only three are considered standardized under the National Highway Traffic Safety Administration (NHTSA).
The horizontal gaze nystagmus test is one of the more widely used. The officer moves an object in front of the driver’s eyes while watching for involuntary jerking, which tends to be more pronounced in people who are impaired.
The walk-and-turn test requires nine heel-to-toe steps along a line, a turn and nine steps back. All of this is done while listening to and following verbal instructions.
The one-leg stand requires the driver to hold one foot off the ground and count aloud. Balancing with the arms and excessive swaying point to impairment.
If a driver’s performance on these tests is going to be used against them, those tests need to have been administered correctly. NHTSA specifies exactly how each test must be done, and if any part of the procedure is changed, the results may not hold up in court.
Anyone who’s charged with drunk driving should determine the role of the field sobriety test in their case. This could be an important part of a comprehensive defense strategy. Working with someone familiar with these matters is often beneficial.