Field Sobriety Tests

Put your left foot on the line and put your right foot in front of it with your right heel touching your left toe. Keep your hands at your side. Do not start until I tell you to. Do you understand? When I tell you to begin, take nine heel to toe steps on the line, turn around keeping one foot on the line, and return nine heel to toe steps, like this. On the ninth step, keep your front foot on the line and turn by taking several small steps with the other foot, like this. While walking, watch your feet at all times, keep your arms at your side, and count your steps out loud. Once you begin, do not stop until you have completed the test. Do you understand the instructions? You may begin the test.

Those are the instructions for the walk and turn test – just one of several field sobriety tests that a cop might ask you to take if you are suspected of a DUI. If you think that sounds like a complicated set of instructions for something you would be asked to do while you’re on the side of the road surrounded by cops in a high pressure situation, that’s probably because it is.

This blog is all about field sobriety tests – what they are, what they are meant to do, and what rights you have regarding them. If you are pulled over for suspicion of DUI, or arrested and charged with a DUI, it’s very important to know the meaning of all the evidence against you, and all your rights regarding how and when you have to provide that evidence. It’s also important to have a good lawyer who understands the ins and outs of field sobriety tests and DUI law.

What are field sobriety tests?

Field sobriety tests (FSTs) are a tool used by law enforcement in investigating DUIs. They are ostensibly designed to help cops determine whether they have probable cause to take the next step in their investigation. Just about any time you are pulled over, a cop is looking for “objective” signs of intoxication – red eyes, slurred speech, smell of alcohol. If they detect any of those, for any reason, chances are they’ll want to do some field sobriety tests next.

In order to do the field sobriety tests, the cops will have you step out of your car. Most of the time, they’ll at least give the three standardized field sobriety tests. Each of these tests is specifically vetted by the National Highway Traffic Safety Administration (NHTSA), and is given by almost every law enforcement agency in the country on DUI stops. Each of these tests has a set of standardized instructions and a set of standard training for cops in how to give them. In the first test, the horizontal gaze nystagmus test, the cop has you follow a pen or other stimulus, in order to see if they can detect clues based on involuntary movements of your eyes; there are three clues for each eye, six total, and theoretically if the cop sees four of those six clues there’s a decent chance of impairment. The other standard FSTs are the walk and turn (see the first paragraph) and the one leg stand – both balancing tests with long sets of instructions, where the cops are looking for just two clues on each to theoretically confirm your intoxication.

There are also several non-standardized field sobriety tests – around Placer County, the common ones are finger to nose, and the modified Romberg, where you lean your head back, close your eyes, and estimate time; the alphabet backwards test is another infamous one. These tests are not scientifically validated or approved by NHTSA, but cops still use them. You may also be asked to take a breathalyzer test, which measures the alcohol content in a deep breath to what is usually a pretty accurate estimate of your blood alcohol level.

Often, at the end of the field sobriety testing, the cops will arrest you, even if you think you did pretty well or don’t think you were above the legal limit. Then you’ll really need that lawyer.

How to win a case with FSTs

The first thing to know about FSTs is that you don’t have to do them. The cops don’t have to tell you that, except about the pre-arrest breath test, but you are not required to do it at all. And given that they are looking for any little slipup to hold against you, there’s no real benefit to you in doing them. Unless you’re on probation (in which case you should’ve learned by now!) the only test you have to do is the post-arrest breath or blood test. Make sure you do that one though, or you could lose your license even if you aren’t guilty.

If you did the FSTs, though, your case can still be defensible. FSTs are merely investigative tools, not designed to hold up as proof beyond a reasonable doubt, especially in a close case. The test is meant to be conducted by trained officers, according to very specific protocols, with the scientifically ideal conditions being in a flat, dry well lit, area. And there are lots of studies that question the scientific accuracy and value of FSTs in the first place.

It's important to know your rights, and if you get in trouble it’s important to have an experienced lawyer on your side who knows all about FSTs and all parts of DUI law.