A police officer pulled you over a night out drinking with your friends at the bar. Your heart drops when you see those flashing lights because you know what is likely going to happen. One step in the traffic stop might be having you complete a field sobriety test to determine if you are likely impaired. You must understand some basic points related to this test if you plan to fight the drunk driving charge that might follow.
#1: Acceptable field sobriety tests are standardized
Field sobriety tests are the basis of some drunk driving defense strategies. A standardized field sobriety test has the endorsement of the National Highway Traffic and Safety Administration (NHTSA). Only standardized field sobriety tests are acceptable for drunk driving cases. This means non-standardized tests aren’t acceptable in drunk driving cases. Police officers may use non-standardized tests in conjunction with standardized tests during a traffic stop.
#2: 3 tests comprise the standardized field sobriety test
The standardized field sobriety test includes three tests. These are the one-leg stand, the horizontal gaze nystagmus test and the walk-and-turn. Together, these tests have at least a 91 percent success rate for determining if a driver is too impaired to drive. The conducting officer must conduct each test in a very specific manner.
Any other tests that officers use aren’t considered part of the standardized field sobriety test. These include saying the alphabet, counting backwards, standing with your head tilted backwards with your feet together or touching your nose while your eyes are closed.
#3: Field sobriety tests are meant to give probable cause for arrest
The purpose of a field sobriety test is to give the officer probable cause to conduct an arrest. Other tests, including a Breathalyzer or blood test, will likely follow the arrest. In Illinois, you must comply with an officer’s request to conduct blood-alcohol concentration testing or you risk losing your driver’s license under the state’s implied consent law.
#4: Training is required to perform field sobriety tests
Police officers must undergo training to conduct a standardized field sobriety test. They must learn how to conduct it and how to determine the results of the test. Each test has very specific markers that the officer must look for when conducting it. The subjectivity of the test result is often the basis of a defense strategy component that some people facing drunk driving charges might opt to use.