Even though a motorist can exhibit clear signs of drunkenness, those staggering behaviors alone may not suffice as evidence in court. Therefore, police will conduct three tests to confirm whether or not a person is intoxicated. These field sobriety tests are the horizontal gaze nystagmus, the one-leg stand and the walk-and-turn test.
Performing the tests
The motorist will perform a series of exercises that will assess their motor coordination and ability to simultaneously follow directions. Many people will readily recognize the walk-and-turn exercise. It entails putting one foot in front of another, walking, counting to nine, turning around and doing the same. While the motorist is doing their best to do as asked, too much alcohol in the system could prevent them from doing so.
During these tests, the attending officer is monitoring behaviors according to their training. For example, two signs of inebriation include losing balance and not being able to touch one’s toes. When a driver is drunk, they will often not be able to perform these tasks successfully. Because these tests can scientifically validate intoxication, positive results will typically be allowed as evidence in a court of law, specifically where the administering officer is trained to conduct these tests.
If a driver does not successfully pass all three tests, they might be asked to take a breath test. This chemical-based test will measure the amount of alcohol a motorist has in their system. If the driver has a blood-alcohol content of 0.08, that is considered drunk, and they will be arrested.
Failing the tests
Not being able to perform the tests doesn’t always mean a driver is intoxicated. Someone arrested for drunk driving may be able to prove that they have a medical condition or other reason for failing the field sobriety tests.