Standard Field Sobriety Tests (SFST) are a group of tests used by the police to ascertain if a driver is driving under the influence. They include a set of tasks that are designed to test for balance and coordination, as well as the ability of a driver to divide their attention or multi-task.
They incorporate a series of tasks that may include the Horizontal Gaze Nystagmus (HGN) test, the walk-and-turn test, and the one-leg stand test. Here’s what each of these tests includes and whether you should take one when offered.
The One Leg Turn Test
For this test, the officer tells the subject to stand with one foot off the ground while counting out loud for about 30 seconds, until they are instructed to put their foot down.
The officer in charge looks for signs of inebriation like, swaying while balancing, using arms to balance, hopping to maintain balance, and putting the foot down before being told to. According to the National Highway Traffic Safety Administration (NHTSA) 35% of the people who get tested (and fail) are not under any external influence.
The Walk and Turn Test
For the walk-and-turn test, the driver is instructed to walk in a straight line, then turn around and walk back in the same direction without falling. The driver must also keep his/her arms at their sides till the test is completed.
This SFST is used to determine a suspect’s ability to follow instructions, consistently maintain balance, and walk in a straight line for an extended period of time. During this test, the officer is on the lookout for, an inability to balance and an inability to follow directions, amidst other signs of intoxication.
According to the NHTSA, 32% of the people who fail this test could be completely sober. A lot of people fail this test, even while sober, this can be explained with a simple fact; majority of people are un-athletic with poor balance.
The Horizontal Gaze Nystagmus Test
This is used to test a driver’s eyes. Nystagmus is the medical term used to describe jumping eyes. The officer asks the driver to follow a slowly moving object, usually a pen or fingertip, from side to side.
Now, alcohol causes Nystagmus, but so do a bunch of other substances as well as naturally occurring conditions. As has been observed in a number of cases, individuals who show signs of naturally occurring nystagmus aren’t even aware of this peculiar condition.
This test is problematic for 2 reasons: first, usage of contact lenses can affect the results. Second, the HGN doesn’t test for alcohol content or intoxication.
The HGN test checks specifically for eye jumping and as previously referenced, but nystagmus can be caused by a lot of different factors, some of which are completely natural.
Should You Take Field Sobriety Tests?
The officers who enforce and score these tests are instructed to write down any “signs” that vary from the standardized criteria. This is interesting to note because the same officers are taught that a significant percentage of the population will show “signs” on these tests (sober or not). However, the test results are admissible as evidence in court, and as a result, they should not to be taken with levity.
Everyone possesses the constitutional right to refuse field sobriety tests, and law enforcement officers know this too. It is well within your constitutional rights to reply the officer with a polite but firm “NO” when asked to take field sobriety tests. When a person takes a field sobriety test, she/he may give evidence against themselves.
But you should know that, due to “implied consent” laws, refusing to take a sobriety test will result in the automatic suspension of your license for one year. Speak to a Washington, DC DUI and traffic offenses attorney to learn more about implied consent laws and how they can affect your case.