The standardized field sobriety test (SFST) is a battery of three separate tests used to determine if a motorist may be driving under the influence. Contrary to popular belief, these tests are not always a clear indication that a person is under the influence of alcohol or drugs. Rather, field sobriety tests are intended to be used to collect evidence suggesting impairment and to establish probable cause for a DUI arrest.
Although jurisdictions throughout the country may use different field sobriety tests during DUI stops and arrests, the National Highway Traffic Safety Administration (NHTSA) regulates three tests that comprise the SFST. These tests include:
Horizontal Gaze Nystagmus
Horizontal gaze nystagmus refers to an involuntary movement of the eyes that happens naturally when the eye look to one side. In a sober individual, nystagmus occurs when eyes are rotated at high peripheral angles. In individuals who are impaired by alcohol and certain drugs, however, nystagmus is exaggerated and can occur at lesser angles.
Walk and Turn
The walk and turn test requires a DUI suspect to listen to instructions and perform simple physical movements that can be easily performed by most unimpaired people. Impaired individuals typically have difficulty with dividing attention between mental and physical tasks. Officers will observe a suspect as they walk heel-to-toe along a straight line and listen to instructions.
One Leg Stand
Another "divided attention" test is the one leg stand test. Suspects are instructed to stand with one foot roughly six inches above the ground and to count out loud until instructed to put the foot down.
Accuracy & Reliability of Field Sobriety Tests
Law enforcement officers will take the results of these tests into account when determining probable cause for arresting a motorist under suspicion of DUI. This being said, it is important to remember that field sobriety tests are not a definitive indication that a driver is under the influence. Adverse weather, slippery roads, unsuitable attire, medical conditions, and many other factors can impact the results of these tests. The fallibility of field sobriety tests as evidence of impairment or guilt can be effectively addressed by an experienced DUI lawyer.
If you or your loved one has recently been arrested for DUI in Orange County – regardless of whether a field sobriety test was performed – retaining legal representation is of the utmost importance. For more information about your case and how the Law Offices of Virginia L. Landry can help, call 877-384-7833.