A field sobriety test is often administered by a law enforcement officer when trying to assess if a person is intoxicated. According to the Massachusetts District Attorneys Association, there are three main field sobriety tests used. These tests have been proven through scientific testing as an accurate way to gauge intoxication and include walk and turn, one-leg stand and horizontal gaze nystagmus.
If you are asked to do the walk and turn test, you will be instructed to walk with your feet heel to toe along an imaginary straight line. You will take nine steps away from the officer and nine steps back towards the officer. He or she will be watching you to assess how well you followed the instructions and to spot any key indicators you may be having trouble balancing, remembering the instructions or carrying out the instructions.
The one-leg stand test is really about balance. You will be instructed to stand with your feet and legs together and raise one foot so you are balancing on the other. As you do this, the officer will be watching to see if you have trouble. Cues that you may be intoxicated include hopping around, putting a foot down, raising your arms to help you balance and swaying.
The final test is the considered the most accurate way to test for intoxication. It is the horizontal gaze nystagmus. This test requires the officer to hold an object about a foot or so in front of your face and ask that you follow its movement with your eyes. The officer will then watch to see if you are following the object accurately. Any delays in following the object or any odd eye movements can be indicators that you are under the influence of alcohol. While this information should not be taken as legal advice, it can help you understand the process and what to expect.