New York’s implied consent law requires drivers in the Empire State to submit to chemical tests to determine whether or not they are operating their vehicles while impaired by either drugs or alcohol, but it does not require them to take a field sobriety test when asked to do so by a police officer. The standardized field sobriety test was developed by scientists working with the National Highway Traffic Safety Administration and the International Association of Chiefs of Police and has been in use since the 1980s, but studies have revealed that it is often unreliable.
The standardized field sobriety test
Motorists who take a standardized field sobriety test actually take three separate tests. Failing these tests is not sufficient to prove impairment in court, but it does give police officers a good reason to request a breath test. The three parts of a standardized field sobriety test are:
- The horizontal gaze nystagmus test is designed to detect involuntary eye movements and is performed by asking the subject to look at a pen or other object as it is moved from side to side and up and down by a police officer.
- The walk and turn test measures coordination and an individual’s ability to follow directions. Subjects walk heel to toe for nine steps and then turn around and repeat the procedure.
- The one leg stand tests balance and is performed by raising one foot about six inches off the ground while counting out loud.
Challenging a field sobriety test
The results of sobriety tests may be excluded when police officers ask DUI suspects to recite the alphabet backwards or perform other tasks that are not part of the official test. This evidence could also be challenged if the subject’s equilibrium and balance could have been affected by their age, weight or a medical condition like an inner ear infection or neurological disorder.
Judging how a motorist performs during a field sobriety test is a subjective process, and police officers should be trained to know how to reliably spot signs of impairment. When law enforcement officers do not receive this important training, this evidence could be challenged and excluded.