Drinking while driving is a crime. Law enforcement who suspect drivers of being impaired may perform traffic stops. The police may do a series of sobriety tests to determine whether a driver is, in fact, drunk.
There are many kinds of sobriety tests. Here’s what you should know about each:
4 kinds of field sobriety tests
The police may begin a traffic stop by having a driver perform field sobriety tests. These tests involve physical activities that are judged by the police. There are three kinds of standardized field sobriety tests:
- Horizontal gaze nystagmus test: The driver follows a finger, pen or light with their eyes and without moving their head.
- One-legged stand test: The driver lifts one leg up slightly off the ground for several seconds.
- Walk-and-turn test: The driver walks in a straight line from heel to toe and walks back to where they started.
Alternatively, the police may ask a driver to do a non-standardized field sobriety test. This can involve, for example, the driver touching their nose and spelling the alphabet backward. The accuracy of these tests can vary depending on if a driver is on prescription medicine or has a disability.
3 kinds of chemical sobriety tests
If a field sobriety test isn’t conclusive, the police may ask a driver to take a chemical sobriety test. There are three kinds of chemical sobriety tests: urine, blood and breath tests. Each of these tests evaluates the alcohol found in the body, which is also called the blood alcohol content (BAC). Out of the three tests, the blood test is often the most accurate and the urine is the least accurate, but breath tests are typically preferable because they can be taken during a traffic stop.
Knowing about each of these tests may be important to you if you are stopped by the police. A traffic stop may not lead to criminal charges, but if it does, you may require guidance as you build a legal defense.