When a police officer thinks you had too much to drink before getting behind the wheel, they will ask you to exit your vehicle during a traffic stop. Then, they will have you perform a series of tasks to evaluate your performance.
These field sobriety tests are often the stepping stone that police officers use to establish probable cause for chemical testing and an arrest for drunk driving. If an officer asks you to perform a field sobriety test, what will they expect you to do?
The one-leg stand
Perhaps the most basic of the standardized field sobriety tests is the one-leg stand. An officer will have an individual suspected of drunk driving put all their weight on one leg and hold the other up with a bent knee. They may also require that the individual answer questions or perform other cognitive tasks while maintaining their balance.
The walk-and-turn test
Alcohol often affects someone’s ability to balance and to walk neatly. Staggering is a common warning sign of intoxication that an officer will use to evaluate you. They will ask you to walk with your feet placed neatly in front of each other in a straight line before turning 180 degrees and coming back to them.
The horizontal gaze nystagmus test
Your eye movements are mostly involuntary, although you can decide where to look when actively thinking about it. A police officer conducting a field sobriety test will have the person taking the test follow their finger from side to side with their eyes to check for a muscle twitch that becomes more pronounced when someone consumes alcohol.
Failing one or all of these tests could lead to a chemical breath test or an arrest. Understanding how the state builds its case that you were drunk while driving can help you defend against those charges.