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What Are Field Sobriety Tests for OUI in Massachusetts?

Updated: Mar 13

If you're pulled over and the officer suspects you of operating under the influence, you may be asked to perform field sobriety tests and other tests. These include horizontal gaze nystagmus (HGN), walk-and-turn, one-leg stand, portable breath test, and post-arrest chemical tests using your breath and/or blood.

If you have been drinking, deciding whether to perform these tests is a crucial decision. Refusing these tests could deny the Commonwealth evidence to convict you of OUI, but refusal can also have consequences for your driver's license. Performing these tests could provide the Commonwealth with evidence to help in your OUI case against you, but it could also prevent driver's license suspensions.

Field Sobriety Tests

Field sobriety tests (or "roadside assessments") are physical tests that help police determine whether you've been drinking. They generally measure your motor skills, ability to follow directions, and ability to do more than one thing at once. These tests include the walk-and-turn and one-leg-stand test.

In the one-leg-stand test, the officer asks you to stand on one leg and hold your other leg up about six inches off the ground. In the walk-and-turn test, the officer asks you to take nine heel-to-toe steps, turn around, then return using nine more heel-to-toe steps.

If you have been drinking, it may make more sense to refuse to perform these tests. If you refuse, there are no consequences for your driver's license under current law, and your refusal cannot be used against you at trial.

Horizontal Gaze Nystagmus (HGN) Test

The HGN test measures the reaction in your pupils to stimuli. The results are not admissible in Massachusetts without expert testimony.

A properly qualified expert such as a drug recognition expert may be able to administer an HGN test and testify to them in court.

Similarly, if you have been drinking, it may make more sense to respectfully refuse the HGN test to deprive the Commonwealth of valuable evidence.

Portable Breath Test

Portable breath tests are conducted with hand-held devices. There are not admissible in court.

You have no right to refuse a portable breath test, and because it's not admissible, it generally doesn't make sense to refuse it.

Breathalyzer or Draeger Breath Test

A breathalyzer or Draeger breath test is administered after arrest at the police station.

If you perform the breath test, it may be admissible against you at trial. If you blow over a .08, this almost definitely proves an OUI case against you.

If you refuse the breath test, it cannot be admitted against you at trial. No one can mention that you refused the breath test or even that you were asked to perform one. On the other hand, you could face a driver's license suspension anywhere from 180 days to life, depending on your history and age.

There is currently pending litigation concerning the reliability of some breath test devices, and some past devices have been proven to be unreliable. If you have a prior OUI with one of these devices, contact an OUI attorney to determine whether your case can be reversed. Contact me today, and I'd be glad to help.

Blood Test

A blood test can be administered at a hospital as part of treatment, if you consent, or if you independently request it.

If you have been charged with OUI in Massachusetts, it's important to contact a Boston OUI defense attorney as soon as possible. Many OUI tests can be excluded from evidence, and you may have a defense to your OUI case regardless. Contact me today, and let's get started on your defense. My phone number is 617-356-8217.