Being pulled over on suspicion of driving while intoxicated can be a distressing experience. The police officer is likely to ask you to perform a series of field sobriety tests. In most states you will be required to take a Breathalyzer test but a field sobriety test is optional.

The Field Sobriety Test is used to determine if there is probable cause to arrest someone for drunk driving. There are three types of official field sobriety tests advised by National Highway and Traffic Safety Administration:

  • Walk and Turn – Also known as walking a straight line, the driver must first watch the officer demonstrate the test, then perform it. It consists of taking nine steps with the heel of one foot touching the toe of the other foot, and then turning and taking nine steps to return to the starting spot.
  • One-Leg Stand – The driver must also watch the officer first demonstrate this test before performing it. The driver must raise one leg about six inches off the ground and count upwards starting at 1,000. (1,001, 1,002 . . .) The driver may have to count up to 1,030 on each leg without swaying or showing signs of poor balance.
  • Horizontal Gaze Nystagmus – The officer holds a pen or other object about a foot away from the participant and watches his or her eyes follow the pen. If the participant’s eyes twitch or jerk around, then it is likely that he or she has been drinking.

Other unofficial tests include counting backwards, reciting the alphabet, and balance-related exercises.

Do I Need to Perform a Field Sobriety Test?

You are not legally required to take these tests. Many lawyers strongly recommend against performing these tests. Since the officer is not likely to ask you to take these tests unless they are already planning on arresting you, there is not much to be gained by going through with them.


Because field sobriety tests are meant to be a scientific basis for determining if a driver has been drinking, their reliability is often attacked. If a test was not administered properly or the driver barely failed, an attorney may be able to make a strong argument against arrest.

When Should I Speak to My Attorney?

Although you can ask to speak to your lawyer after being pulled over by the officer, most states do not give you the right to consult an attorney until after you have been arrested. Once you are arrested you can, and probably should, ask for your lawyer immediately. An experienced criminal defense attorney can let you know your rights and prepare your defenses.