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New Hampshire And Massachusetts

The role of field sobriety tests in DUI arrests

A DUI arrest often feels like a life altering experience. Not only are you facing the potential of losing your driving privileges, but you could also have to pay fines and spend time behind bars. However, the events leading up to your arrest could play an important role in your defense. This is because field sobriety tests might not be as accurate as they seem.

New Hampshire police officers rely on a number of different sobriety tests when making an arrest for drunk driving. Breathalyzer tests measure a person’s blood alcohol content based on breath and are perhaps the most well-known type of sobriety test. There are also blood tests that authorities can use to determine BAC.

What are field sobriety tests?

The National Highway Traffic and Safety Administration endorses the Standardized Field Sobriety Test. The SFST actually consists of three different tests intended to measure different indicators of intoxication. These three tests are the:

  • Horizontal gaze nystagmus
  • Walk-and-turn
  • One-leg stand

Officers generally do not use these tests in isolation from one another. Instead, when an officer suspects that a driver might be under the influence of alcohol, he or she will ask the driver to participate in all three tests. Performing poorly on one of these tests but well on the other two is not necessarily an indication of intoxication.

How the tests work

Everyone’s eyes naturally make an involuntary jerking movement when gazing to the side. That jerking tends to be exaggerated in those who are under the influence of alcohol. The horizontal gaze nystagmus test looks at possible exaggerated eye jerking as well as whether the driver is able to follow a moving object.

Since those under the influence of alcohol sometimes struggle to follow a task with divided attention, the walk-and-turn measures a driver’s ability to do just that. The test involves a driver taking nine steps in a heel-to-toe fashion, while maintaining a straight line. He or she must then turn and walk back in the exact same manner.

Watching your balance

The one-leg stand test measures balance. An officer who is performing this test will ask a driver to stand with one of his or her feet six inches off of the ground for a period of 30 seconds. During this test, the officer will specifically look for:

  • Swaying
  • Using arms for balancing
  • Hopping
  • Placing one foot down

Police officers are only human, which means that they can incorrectly interpret the results of field sobriety tests. If you were arrested in part because of your own performance in such sobriety tests, you might even be able to call into question the validity of your arrest. This is just one approach to DUI defense though, so you should be sure to explore your other options for minimizing the potential impact of a conviction.