Field Sobriety Tests, also known as FSTs, created by the National Highway Traffic Safety Administration (NHTSA). They were designed to help police determine if a person is impaired by alcohol. Three main tests are used, normally in addition to a Portable Breath Test (PBT). The results of these tests are used to establish Probable Cause to request a blood test or more reliable breath test.
The three main FTSs are:
- Horizontal Gaze Nystagmus (HGN) Test: This test is done with a pen or small light to examine the movements of the pupils of the eyes. If your pupils involuntary move during this test it could be a sign of impairment.
- Walk and Turn Test: This test is a nine step, heel to toe, straight line walking test, and is used to measure coordination and balance to show signs of impairment.
- One Leg Stand Test: This test involves standing on one leg with the other leg about six inches off the ground, while counting out loud. This test is also used to measure coordination and balance to show signs of impairment.