Indiana police use standardized field sobriety tests when they suspect a driver is impaired. The National Highway Traffic Safety Administration developed these tests. Officers use them to check for signs of impairment during a traffic stop.
Understanding how the three standardized field sobriety tests work can help you better understand the evaluation process and what officers look for when investigating suspected impaired driving.
How does the horizontal gaze nystagmus test work?
The horizontal gaze nystagmus test is often the first field sobriety test officers administer. During this test, the officer asks you to follow the movements of a small object with your eyes. You must also keep your head still. The officer watches for involuntary jerking movements in your eyes, which can indicate impairment.
When a person consumes alcohol, their eyes may exhibit nystagmus or jerking movements at certain angles. The officer looks for three specific clues in each eye:
- Whether your eye can follow a moving object smoothly
- Whether jerking is distinct when your eye moves to the side
- Whether your eye starts to jerk before it reaches a 45-degree angle
These observations help officers evaluate possible signs of impairment. They form one part of the overall field sobriety assessment.
What happens during the walk-and-turn test?
The walk-and-turn test asks you to take nine steps that are heel-to-toe in a straight line. Then you turn around and walk back the same way. The officer provides instructions and demonstrates the test before asking you to perform it. During this test, keep your arms at your sides and count each of your steps aloud.
This test evaluates your ability to follow directions and maintain balance simultaneously. Officers look for numerous indicators of impairment, which generally include:
- Starting early before the instructions finish
- Losing your balance
- Stepping off the line
- Using your arms for balance
- Taking the wrong number of steps
- Turning incorrectly
Officers consider these actions when assessing overall performance. Even small mistakes may be noted during the evaluation.
What does the one-leg stand test measure?
The one-leg stand test asks you to stand on one foot about six inches off the ground. You then count out loud for 30 seconds. You must keep your arms at your sides and watch your elevated foot during the test. This test checks your balance and your ability to follow instructions while moving. Officers typically watch for four specific indicators:
- Swaying while balancing
- Using your arms for balance
- Jumping to help you keep your balance
- Putting your foot down before the 30-second mark ends
These behaviors may show poor balance or trouble focusing. Officers document their observations as part of the investigation.
Understanding your options during a traffic stop
Knowing the three field sobriety tests can help you handle a traffic stop with more knowledge and confidence. By knowing what officers look for during each assessment, you can gain a clearer understanding of how impairment evaluations work. This way, you can put yourself in a position to make safer, more informed decisions in case the police pull you over.
