A law enforcement officer who has reason to believe that you may be driving while intoxicated can pull you over. However, he or she has to collect evidence of your intoxication before arresting you for DWI.
There are many different assessments available to help authorities collect this evidence. For example, a law enforcement officer may ask you to perform a battery of field sobriety tests.
What are field sobriety tests?
When an officer performs field sobriety tests, he or she asks you to perform one or more tasks that would be difficult to perform in a state of intoxication. The officer gauges your performance on these tasks and draws a conclusion about your current state of intoxication based on your performance.
Are field sobriety tests legal?
It is legal for a law enforcement officer to ask you to perform field sobriety tests, such as touching your nose with your finger with your eyes closed, counting backward or identifying how many fingers the officer is holding up. However, while it may be legal for an officer to perform assessments such as these, the evidence collected in the process is not always admissible in court.
What are SFST?
According to FindLaw, standardized field sobriety tests are three assessments that research has shown to be accurate at indicating driving impairment because of alcohol. The one-leg stand test and the walk-and-turn test measure your balance and coordination, while the horizontal gaze nystagmus test measures an involuntary jerking of your eyeball that becomes more pronounced under the influence of alcohol.
For the results of the standardized field sobriety tests to be reliable, you have to complete all three of the assessments.