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Never Plead Guilty Based on Field Sobriety Tests That Use Faulty Science

3834505031_fc87e26232_mPolice officers rely heavily on field sobriety tests when they suspect a driver of being intoxicated. Unfortunately, as a Massachusetts drunk driving defense attorney, I know that there are serious problems with these tests, and I use those problems as an element of my clients’ defense whenever appropriate. The appeal of field sobriety tests is clear: Drunk driving is dangerous and law enforcement agencies need easy-to-use, scientifically and legally valid ways of identifying drunkenness. Unfortunately, the field sobriety tests that are most commonly used in Massachusetts aren’t as reliable as they should be, and may not be administered properly. This means that completely innocent drivers who haven’t even had one drink can sometimes be arrested for driving under the influence of alcohol.

The National Highway Traffic Safety Administration (NHTSA) recommends three specific field sobriety tests — the horizontal gaze nystagmus test, the walk-and-turn test, and the one-leg-stand — as the most reliable ones for police officers to use. The NHTSA says that police officers who use all three tests on a suspected drunk driver have a 91% chance of making the right call as to whether or not the driver is actually drunk. In what the NHTSA views as the most accurate one, the horizontal gaze nystagmus test (or “jerking eyeball test”), a police officer asks a driver to follow a small flashlight side to side with his or her eyes. If the driver is drunk, his or her eyeballs shake as they look to the side. The walk-and-turn test is similar to walking a balance beam back and forth on a straight line. And the one-leg stand involves perhaps the greatest physical challenge of the three: drivers are asked to stand still with their arms at their sides, raise one leg six inches off the ground while keeping it straight and pointing at their toes, looking at their raised toes, and count forward from 1,001. Swaying, raising arms for balance, hopping, putting the foot down, or starting to count before the police officer tells them to can all be viewed as signs of drunkenness.

Several years ago, the Washington Post ran an article about the faulty science behind these tests that I found fascinating, as a Massachusetts OUI defense lawyer. The scientific basis of field sobriety tests lies in a 33-year-old study of how well field sobriety tests could identify blood alcohol content. That study was conducted with 238 subjects, mostly men 22-29 years old, and no control group. As the article sums up, “So hundreds of thousands of drivers have been arrested — no doubt many deservedly so — on the basis of a 30-year-old study that, critics argue, has never been published in a peer-reviewed, scientific journal, never tested on a large scale with a control group and, perhaps more astonishing, has nothing to do with actual impairment from alcohol.”

Besides the tests’ scientific faultiness, they can also falsely identify as drunk people who just have medical issues. Balance disorders affect 40% of Americans at some point in their lives, and dizziness and vertigo are the third leading cause for visits to doctors. The older you get, and the heavier you get, the worse your balance. For an aging population with a growing number of overweight and obese people, the one-leg stand test sounds like a pretty ineffective gauge of whether someone is drunk.

This is why it’s important for anyone facing OUI charges to contact a Massachusetts intoxicated driving criminal defense lawyer immediately. Experienced OUI defense attorneys know how to legally challenge unreliable field sobriety tests and get that evidence thrown out, which can get the charges dismissed or help win a not-guilty verdict. Anyone accused of a crime with serious penalties like OUI should avail themselves of the expertise of a criminal defense lawyer like Stephen Neyman.


For a free phone consultation on defending yourself against drunk driving charges in eastern Massachusetts, please call the Law Offices of Stephen Neyman, located in downtown Boston, at (617) 263-6800. You can also send us a message online.