Follow the penlight with your eyes. Stand on one leg and count the seconds that pass. Walk in a straight line, pivot, and return.

These three standardized field sobriety tests are often portrayed as part and parcel of a suspected drunk driving traffic stop. While it is true that authorities frequently administer them, if you’re pulled over and asked to execute any of the tests, do you actually have to do so?

Field sobriety tests are not mandatory

Let’s start with the simple truth. No matter how many times a law enforcement officer asks, you do not have to perform these standardized tests. There is no direct penalty for respectfully declining to participate, even if the officer makes it sound as though you must take part.

It’s also worth noting these tests are not always reliable indicators of impairment. Someone could have trouble completing a one-legged stand, for example, because of a physical condition. Or they might simply be nervous after an officer stopped them.

There is one thing to keep in mind. If you refuse a standardized test and your case goes to trial, the fact that you refused could potentially be used against you in court.

Why do officers ask drivers to do these tests?

If a driver can lawfully refuse to take these field sobriety tests, why do officers routinely request them? It’s all about strengthening authorities’ potential drunk driving case. Any evidence gathered from these tests (often performed before an arrest is made) can be used against the driver in a criminal trial.

Essentially, these three standardized field sobriety tests don’t really exist to help you prove you are sober. Rather, they’re used as a way for law enforcement officers to gather more information that supports their side of the story – that you’re drunk.

At the end of the day, you rarely have anything to gain by consenting. Rather, it’s the authorities that truly stand to benefit as they look to build their case against you.