What is a field sobriety test?

| May 31, 2019 | OUI Defense

When stopping a suspected drunk driver, police will look for evidence of impairment. A 3-part field sobriety test is a typical method and its execution needs to be addressed in an OUI defense.

First, the horizontal gaze nystagmus test checks the involuntary jerking of an eyeball when an object is moved side to side. An impaired driver’s side-to-side gaze will reveal substantial jerking.

A police officer will move their hands from side-to-side and will ask the driver to follow their fingers or a small flashlight or pen. They will determine whether the driver’s eye cannot smoothly follow the object, whether the jerking is sustained and whether the jerking begins before the eye is 45 degrees of center.

Next, the walk-and-turn test requires the driver to take nine steps in a heel-to-hoe fashion, turn on one foot and come back in the same way. Police look for several things such as whether the driver is unable to keep their balance, starts before instructions are given, steps to regain balance, makes an improper turn, takes an incorrect number of steps or steps off a straight line.

Finally, the one-leg stand test has the driver stand with one foot approximately six inches from the ground and count aloud beginning by 1,000 until the police tells them to put their foot down for 30 seconds. Police look for swaying while trying to balance, using arms to balance, hopping and putting the non-weight-bearing foot down.

There are some flaws with these tests, which do not measure blood alcohol content. It is unlikely they are administered and scored uniformly. Police have usually decided that the driver is impaired whether they made the stop and use the test to determine whether probable cause supports their decision. Any performance that is not perfect may be scored as a failure.

Under Massachusetts law, it is not mandatory to comply with these tests, but refusal may likely lead to suspicion that the driver is hiding something and to an arrest. Passing the test may still lead to a breathalyzer test. Having a moderate amount of alcohol can also lead to a test failure.

Seeking legal representation immediately can help protect rights. An attorney can provide guidance and challenge any flaws with these tests.