What are Field Sobriety Tests?

December 7, 2016


Attorney Mike Bowser of Bowser Law speaks with John Maher about the uses and limitations of field sobriety tests. Field sobriety tests can be difficult or impossible for some people regardless of intoxication, and they may not be given in proper conditions. This can greatly affect your DUI case and its verdict.

John Maher: Hi, I’m John Maher. I’m here today with Mike Bowser, a board-certified DUI defense lawyer practicing in Massachusetts and New Hampshire. Today, we’re talking about field sobriety tests. Welcome, Mike.

Mike Bowser: Good morning.

John: So Mike, what are field sobriety tests and why are they performed?

Mike: Field sobriety tests are exercises, and a police officer who’s testifying before a judge or a jury will always describe them as “divided attention” tests. What they are designed to do is give the police officer an indication or evidence of possible impairment by alcohol. For instance, the standard three that you usually see in Massachusetts and New Hampshire is what’s called a horizontal gaze nystagmus test where an officer holds a pen or his finger about 12 or 15 inches away from your face, moves it in a horizontal plane in front of your face, and asks you to track it with your eyes only, without moving your head.

Then, he’s looking for an involuntary horizontal jerking of the eyeball as it tracks that stimulus, because he has been trained that certain presentations in the the eyeball as it tracks the stimulus can be indicative of alcohol impairment. Then, the other two that you always see are a heel to toe walk and turn test where you’re are asked to stand heel to toe and then walk nine steps on a line, turn in designated fashion, and walk nine steps back keeping your hands down at your side and touching each step heel to toe in a straight line.

John: That’s the one you always see on TV and things that would-

Mike: Yes.

John: -walk the line, yes.

Mike: The last one is a balance. A true balance test where you’re asked to stand at attention. It’s the one-leg stand. You stand at attention with your hands down by your side and when you’re asked to begin, you raise one foot of your choosing six inches off the ground pointing your toe, looking down at the toe of your foot and then you count one one-thousand, two one-thousand. That counting is an instruction, but the officer is actually timing the test looking for you to keep that foot elevated for a period of 30 seconds.

John: Are there any tricks to it? Like the actual test just to see whether or not you can count one one-thousand, two one-thousand? It’s not really about the balance at all or is it-

Mike: No.

John: -a combination of those things?

Mike: It’s absolutely a combination. He’s looking for is both a physical component and a mental component. Mental meaning “can you actually absorb the verbal instructions that he’s given you and then execute those instructions?” Are you able to follow directions and execute the instructions as they were given to you mentally? Then physically, are you capable of doing what they will refer to as “simple balance walking exercises?” Clicking heel-to-toe, keeping your foot elevated, not using your arms for balance, staying on the line, don’t sway, and don’t hop. Quite frankly, I believe that the tests are designed to fail because they are incredibly difficult, put in context. They’re typically given roadside, you could be standing on the side of 128 or the breakdown lane of 93 North or Route 3 at two o’clock in the morning with traffic and trucks zipping by under the scrutiny of a police officer with his flashlight, his uniform, his flashing lights. It can be very difficult.

Every person is different, some people are more gifted in terms of their coordination, their balance, their athletic ability. Some people are not. There are restrictions related to these tests based on back injuries, leg injuries, inner ear disorders, weight, whether you’re more than 50 pounds overweight or not, the type of shoes that you’re wearing, do you have on a heel. All of these things factor into the validity of these tests to actually, truly reflect a person’s impairment by alcohol. Or are they just nervous, scared, embarrassed, afraid, clumsy? All of those things.

John: Right. Sure, anytime I’ve been pulled over for speeding or something like that I take off after the police officer lets me go and my leg is shaking. I’d have to imagine if I was trying to walk the line or something like that, yes, my knees would be shaking.

Mike: I’ve had the same experience. I was pulled over coming from a hockey rink at 8:30 in the morning and I think my hand was shaking as I emptied my wallet to hand over my license for no reason. I had done nothing wrong.

John: Right.

Mike: But merely the presence of a police officer at your window can be a nerve-wracking experience for any driver. Then, you ask that driver to step from the vehicle and perform a physical, mental task that is very unfamiliar to them. As I tell juries all the time, field sobriety tests are familiar rote activities for one class of people and one class of people only: police officers.

John: Right.

Mike: Because they see them and demonstrate them and instruct them all the time.

John: They just think it’s the most simple thing. Everybody should know how to do that.

Mike: Given their experience and exposure and practice for them, it is. But for most drivers it is not.

John: Right. Is it your opinion then that field sobriety test results are unreliable?

Mike: I don’t think they’re reliable for most drivers as an indicator of impairment, given the level of emotional stress that may be involved, given the physical characteristics and the differences between one person to the next. There are so many factors that go into whether a person is having difficulty with that test because of alcohol, because of emotional stress, because of physical limitations, or disabilities.

All of those things need to be explored and that’s typically what you see in a courtroom in terms of cross-examination. The officer will quite readily admit that there are limitations to these tests and oftentimes they’re not factoring in exactly what they’ve been trained to factor in–injuries, disabilities, overweight, heels, the conditions where the test were given, the weather, the surface, whether it’s wet, icy, snow, wind, rain–all of these things factoring.

John: Right. Can field sobriety tests then be challenged in court?

Mike: Absolutely. I would say that 95% of my trials are trials involving a motor vehicle stop with those battery of field sobriety tests being given. I’m always asking a judge or a jury to consider the validity of those tests. And I’ve had many not guiltys where the officer’s opinion was that my client failed each and every one of those field sobriety tests, but that wasn’t sufficient evidence for a judge or a jury to find impairment beyond a reasonable doubt based on those tests alone.

John: Okay. How can an attorney help in this situation?

Mike: If you are familiar with the testing and the training behind the testing, then I think that leads to an effective cross-examination of a police officer. If you know the police officers’ training as well as he does, you should be able to effectively bring to the fore the limitations in the testing. Whether they were done properly and whether they were done as he was trained to do them.

You need to be as familiar with those tests as that officer is. You need to be familiar with his training. There’s a manual that is provided to police officers in Mass and New Hampshire through the Academy based on what’s called the National Highway Traffic Safety Administration Guidelines for Field Sobriety Testing. I have each and every one of them since the ’80s and I know them very well. You need to, in order to effectively defend someone who has been subject to field sobriety test.

John: All right. Because like you said, they are trained in those manuals to take into account factors that may affect the test.

Mike: Sure.

John: Somebody is like you said wearing heels and is overweight and is being asked to stand on one foot. It seems that would be awfully difficult and yet they may not be taking that into account when they determine that that person is intoxicated.

Mike: Sometimes the officers…for instance the walk and turn test. If you read the manual, the walk and turn test requires a designated straight line. Well, oftentimes the only designated straight line that is available to the trooper or the officer is the breakdown lane on the highway. They’re never going to put someone on the breakdown lane.

John: Standing right on the edge of the road.

Mike: Exactly, just for safety purposes. There are some certain limitations to their ability to do things perfectly. Now, that doesn’t mean they’re intentionally deviating from their training but it’s important to point out to the jury that, “Listen, you were trained to use a designated straight line, you didn’t have one available to you, how do you account for that in your opinion?” Oftentimes they’ll say, “Well, I considered it,” and, “Well, how did you consider it? Because you’ve certainly testified under oath that he failed but one of the key components of your training was not part of this test.” You need to look at where the tests were given, when they were given, under what conditions they were given.

John: Right. All right. That’s great information, Mike. Thanks again for speaking with me today.

Mike: Sure.

John: For more information about Mike Bowser, visit bowserlaw.com or call 888-526-9737.

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