Three Accepted Types of Field Sobriety Tests

In order to make a lawful DUI arrest, law enforcement must establish “probable cause,” which is a reasonable suspicion that a crime has been committed based on their observations. However, a swerving car or slurred speech isn’t always enough to “reasonably” convince an officer that someone is most likely intoxicated. As such, officers often turn to the tools at their disposal, field sobriety tests, in order to make this distinction and place someone under arrest.

A field sobriety test is a small task that’s designed to test someone’s intoxication level. For many years, field sobriety tests were as widely varied as their results, and this led to extremely inaccurate and wrongful arrests. Today, after extensive study and refinement, there are three widely-implemented and utilized field sobriety tests that officers use, however, they’re not immune from error as well shall explain.

Horizontal Gaze Nystagmus Test

The horizontal gaze nystagmus test is perhaps the most widely-used field sobriety test because of how easy it is to conduct and how reliable it is. Unlike other tests which check for divided mental capacity to prove intoxication, this test looks for something even simpler: your brain’s ability to control your muscles. In this test, an officer holds up a pen, their finger, or a small light to right about your eye level and then asks you to follow it without moving your head. That’s it, it’s that easy.

The officer conducting the test will carefully watch your eyes while moving the object back and forth. If you’re intoxicated, you’ll lose the ability to effectively control the muscles in your eyes causing them to occasionally twitch or move erratically. While you may feel fine and not even recognize you’re doing it, it’s a dead giveaway to the officer conducting the test. Of course, sometimes people with attention disorders or who are easily distracted spot something that catches their eye, which causes their eyes to twitch, even though they aren’t necessarily intoxicated. Therefore, this test isn’t perfect.

Walk & Turn

The walk and turn test is another fairly common tool officers use, but it’s different in that it forces you to concentrate on two separate tasks rather than checking for your muscular ability. In this test, the officer will have you walk heel-to-toe (kind of like you were on a balance beam) for a certain number of steps, before turning without lifting your feet and then walking back. In this test, officers are testing your ability to concentrate and balance on walking as well as your ability to handle the mental task of counting how many steps you’ve taken and then remembering to turn appropriately.

Sound hard? It’s supposed to be, and it is, but unfortunately the difficulty of the task means that many people can’t do it, even while completely sober. This means a number of people are arrested and falsely accused of driving under the influence when in reality they’re completely innocent and their breathalyzer or blood alcohol content test likely backs that up.


The one-leg-stand test is similar to the walk and turn test in that it presses someone’s ability to perform a mental and physical task simultaneously, which becomes immensely more difficult when intoxicated. In this test, the officer will instruct you to stand on one leg with your toe pointed and then count to thirty (usually by the “one-one thousand, two one-thousand, three one-thousand” method).

As you can imagine, this is another task that can be extremely demanding, even while sober. If you struggle to balance for more than a few seconds, you’ll probably fail the test. Likewise, sometimes people forget to count properly or don’t count slow enough, or show any number of other faults. Because of this, as you can imagine it’s perfectly possible for this test to yield a false positive and lead to a wrongful arrest.

If you have been arrested and think the officer who arrested you may have done so in error, speak with a Fort Lauderdale DUI lawyer today by calling Hager & Schwartz, P.A. at (954) 840-8713!