When stopped on a DWI charge in New York, the investigating officer will conduct what are known as “Standardized Field Sobriety Tests.” (SFTS) These tests are utilized by law enforcement officers to establish probable cause prior to the arrest of a driver who is suspected of operating a vehicle while intoxicated. A standardized field sobriety test is one of three separate tests which were designed to, and allegedly can successfully, predict a driver’s level of impairment. The SFST was created based on National Highway Traffic Safety Administration (NHTSA) research. The NHTSA sponsors a formal field sobriety test training program designed to teach police how to more accurately detect individuals who are potentially driving while intoxicated (DWI). The NHTSA’s field sobriety test program is administered by the International Association of Chiefs of Police.
The three components of a standard field sobriety test are the horizontal gaze nystagmus (HGN), the walk-and-turn (WAT), and the one-leg stand (OLS). HGN testing evaluates an allegedly intoxicated driver’s natural eye movements. The human eye involuntarily jerks when gazing too far to the side. In an allegedly intoxicated driver, the natural jerking motion occurs at a lesser angle than under normal circumstances. During the HGN, a police officer will evaluate how a driver’s eyes track a slowly moving object such as a flashlight or pencil. Throughout the exercise, the officer is examining whether the driver has the ability to follow the object smoothly and at what angle involuntary jerking of the eye occurs. According to NHTSA research, the HGN is capable of accurately predicting a blood alcohol concentration (BAC) of .08 (the standard for intoxication in New York and many other states) about 88 percent of the time. This testing may not successfully establish alcohol impairment, however, as seizure medications and other drugs can also affect a driver’s ability to track slow moving objects. Further, if the driver has allergies or recently suffered a concussion, (which the officer is required to inquire about but often do not), the test results will likely not be accurate.
Both the WAT and OLS tests are “Divided attention tests”< which measure both the driver's ability to perform physical tasks and follow instructions at the same time. Both examinations require an allegedly intoxicated driver to simultaneously listen, follow instructions, and perform specific physical movements. Normally, most individuals who have consumed alcohol will find the tasks more difficult to perform than those who have not.
A WAT test requires a driver to take nine heel-to-toe steps along a straight line, turn on one foot and repeat the exercise in the opposite direction. During the test, a law enforcement officer is examining a driver’s balance and ability to follow directions. According to NHTSA research, a failed WAT test accurately predicts a blood alcohol level of .08 approximately 79 percent of the time. An OLS examination requires a driver who is suspected of being intoxicated to stand on one foot and count aloud for about 30 seconds. During the test, a police officer is again watching the driver’s ability to maintain their balance. According to the NHTSA, the OLS test can accurately predict a blood alcohol level of .08 in approximately 83 percent of cases.
A DWI charge in the State of New York can result in serious repercussions for a driver. Most individuals who are accused of DWI fear they will lose their driving privileges, or are concerned that losing their license will cause a loss of employment and consequential implications for their families. If you are charged with DWI felony DWI under Leandra’s Law or any other impaired driving charge, you need to consult with a knowledgeable criminal defense lawyer as soon as possible.