When police suspect someone is driving under the influence of a substance, often after noticing strange or reckless driving patterns, they’ll use a few tools to evaluate a driver’s intoxication level.
Often, police will ask a driver to step out of their vehicle and perform a few standardized field sobriety tests (SFST). These tests allow police to judge a person’s intoxication level by their ability to successfully complete the tests (or not). There are three commonly used SFSTs:
1. Horizontal gaze test
Police may be able to judge a suspect’s intoxication level by the movement of their eyes through a horizontal gaze test. The suspect would be asked to follow a single point, like a flashlight or finger, with just their eyes. Any deviation, straying or delayed movement may indicate the suspect was drinking.
2. Walk-and-turn test
Another test that police may use is the walk-and-turn test, where the suspect is asked to walk in a straight line and walk back to where they started. This test may indicate that the suspect was drinking if they aren’t able to walk in a straight line, stumble, fall or don’t correctly follow instructions.
3. One-legged stand test
Alternatively, a suspect may have to do a one-legged stand test. This test, simply, calls for the suspect to stand on one leg to test their balance. Falling or having difficulty following directions may make police suspect the driver is intoxicated.
SFSTs aren’t required by law – which many people don’t realize. They’re often used to justify further investigation and (eventually) a drunk driving arrest. Because they’re subjective, they may lead to false DWI charges. You need to know your options when building a strong defense against a DWI charge.