Maryland Field Sobriety Tests

The Standardized Field Sobriety Test (SFST) was created in the 1970s as a means for law enforcement officials to observe and measure the impairment levels of people who are pulled over on suspicion of drunk driving. The National Highway Traffic Safety Administration (NHTSA) sponsored the research for the test, which was conducted by the Southern California Research Institute. The SFST is a combination of three separate tests that are used by police officers to determine whether a driver has been operating a motor vehicle under the influence of alcohol or drugs. The NHTSA as concluded that the tests demonstrate sufficient reliability, therefore they are now admissible in court.

Standardized Field Sobriety Tests in Maryland

The SFST has three parts that are meant to be administrated in conjunction with one another. When all three parts of the test are performed together, they are supposed to be exceptionally reliable and serve as additional confirmations of the result of one test. The first test is known as the horizontal gaze nystagmus test (HGN), the second is the walk-and-turn test (WAT) and the final one is the one-leg stand test (OLS). The problem with the field sobriety tests is that they are extremely difficult to perform even when a person is sober, therefore the results of the tests can often be misconstrued by police officers.

Horizontal Gaze Nystagmus (HGN)

The horizontal gaze nystagmus test involves an officer closely watching the eyes of a driver as they follow a stimulus in order to detect a certain “jerking” of the eye. The stimulus could be any object, but is typically a pen, flashlight, or the officer’s finger. Nystagmus is a slight shaking that occurs when the eyes move from side to side, and it is exaggerated in people that have consumed alcohol. A person will not know that they are exhibiting nystagmus, but the officers are trained to detect when this shaking occurs and the eyes cannot smoothly track the stimulus. Unfortunately, there are other factors that could cause a person to exhibit nystagmus, therefore this test is not completely reliable as an indicator of impairment.

Walk-and-Turn (WAT)

The walk-and-turn test is a divided attention test that involves a person walking nine steps, heel-to-toe, in a straight line, and then turning and walking in the same manner back in the opposite direction. Drivers who are impaired often cannot walk straight and may have trouble balancing or following the officer’s instructions. One main problem with the walk-and-turn test as a measure of driver impairment is that physical factors, such as a person being overweight or wearing high-heeled shoes, can impact their ability to perform this test properly.

One-Leg Stand (OLS)

The third part of the Standardized Field Sobriety Test is the one-leg stand. This test requires a person to lift one foot approximately six inches off the ground and balance on one leg for 30 seconds with their hands at their sides and without dropping their foot. They are usually also required to count to thirty while they balance on one leg and try not to fall over. Officers conducting the one-leg stand test will watch for signs of swaying, hopping, or general imbalance as indicators of intoxication. For people who have certain medical conditions that effect their equilibrium and their ability to balance normally, this test can be extremely difficult even in sober conditions.

Talk to a Maryland DUI Attorney

The Standardized Field Sobriety Test is claimed to be extremely reliable as a means to detect a person’s impairment level. Unfortunately, there are many issues with the battery of tests that make up this detection system and officers can often mistake a person’s results for impairment when they are not, in fact, impaired at all. If you have been accused of a drunk driving-related offense and you have questions, contact Maryland DUI attorney Seth Okin to explore your options for defense. Call his law office today at (410) 782-0742 for a free case evaluation.