It’s late, and you’re driving home after a long day. You’re tired, but you’re sober. Just a few more minutes, and you’ll be in bed. Then—flashing blue lights in your mirror. You pull over, heart racing. The police officer walks up, shines a flashlight directly into your eyes, and starts asking questions. “Where are you coming from? Had anything to drink?” You fumble through your answers, trying to stay polite.

Then comes the kicker: “Do you mind stepping out of the car and perform some tests for me? Just to make sure you’re safe to drive.” Before you know it, you’re walking heel-to-toe down an imaginary line, wobbling on one foot like you’re trying to join Cirque du Soleil. Your heart sinks as you realize how ridiculous this looks. The officer scribbles notes, and you start to wonder—am I failing this even though I haven’t had a drop to drink?

This situation plays out all too often. Many drivers don’t realize these field sobriety tests (FSTs) are completely voluntary in most states. Refusing to take one might actually be the smarter move.

What are field sobriety tests?

Field sobriety tests are a series of physical tasks meant to help officers decide if you’re under the influence. The tests include the walk-and-turn, one-leg stand, and horizontal gaze nystagmus (where you follow a moving object with your eyes). They sound simple, but nerves, fatigue, or even medical conditions can make passing them tricky—even for sober drivers.

These tests aren’t even that reliable. According to Justia, they accurately identify drunk drivers in only two-thirds to three-fourths of cases. That means a lot of sober people fail due to factors like anxiety or poor balance.

Attorney Andrew Flusche pulls no punches, calling FSTs “a joke.” He warns, “Officers asking you to perform field sobriety exercises are asking you to give them evidence that will likely incriminate you.” In short, these tests are not designed to clear your name—they’re designed to justify an arrest.

Why refusing might be smarter

In most states, you have the right to decline a field sobriety test without facing legal consequences. If asked to perform one in these states, you can politely decline and say, “I invoke the Fifth Amendment.” Then stay calm and quiet.

If the officer presses on, you may also be asked to take a roadside breathalyzer test. Like FSTs, these handheld tests are voluntary in most states. Refusing them won’t result in penalties. The accurate breathalyzer test at the station, however, is another story. Under implied consent laws, refusing this post-arrest test can lead to fines, license suspension, or other consequences. But if you refuse the FST and roadside breathalyzer test, the investigating officer is forced to first arrest you with other evidence–such as sloppy driving or slurring words.

Bottom line: Know your rights

Field sobriety tests—and most roadside breathalyzers—are voluntary. Agreeing to them can only add evidence against you. If pulled over, remember your rights: you can politely decline and invoke your right to remain silent.

Knowing what’s required and what’s not is key to protecting yourself. Stay calm, don’t give officers unnecessary evidence, and consult a local lawyer if you face charges. In situations like these, staying informed is your best defense.

You can see Andrew Flusche’s explanation of field sobriety tests in the video below: