What You Should Know About DUI Field Sobriety Tests

April 11, 2020
DUI Field Sobriety Tests

If you become the subject of a DUI investigation, it is important to know what to expect. A major part of any DUI investigation is the battery of field tests that a police officer might ask you to perform. These exercises are called Standard Field Sobriety Tests, or SFSTs. Leaning about what to expect with SFSTs from a Fairfax Virginia DUI Defense Attorney now is critical since you have no right to consult with legal counsel immediately prior to performing these roadside tests.

The first and most important thing you should know about SFSTs is that they are completely voluntary. This means that if you do not want to or do not feel comfortable performing them, you may politely refuse to do so. Do not feel under any obligation to perform SFSTs or to make any statements to the police officer that make you uncomfortable or might be incriminating.

NHTSA Approved Tests

There are three SFSTs approved by the National Highway Traffic Safety Administration (NHTSA): the Horizontal Gaze Nystagmus, the 9-Step Walk and Turn, and the One Leg Stand.

  • Horizontal Gaze Nystagmus, or “HGN,” is a test that focuses on the suspect’s eyes. The police officer will hold a stimulus, usually a pen or their index finger, in front of the subject’s face and smoothly move it from side to side. While doing this, the officer is looking for involuntary jerking of the pupils in each eye and at different points in the suspect’s range of vision.
  • 9-Step Walk and Turn is a divided attention test, combining verbal recitation with physical movement. The officer will have the subject stand with one foot immediately in front of the other during the instructional phase of the test. The officer will use a line in the road or an imaginary line and direct the suspect to take 9 heel-to-toe steps out on that line, turn around making a series of pivot steps, and take 9 heel-to-toe steps back on that same line. The suspect is told to count their steps aloud 1 through 9 out and 1 through 9 back. The suspect is also told to keep his/her arms by their side throughout the test.
  • One Leg Stand is also a divided attention test, mixing recitation with balance. The officer will have the subject stand with feet together and arms by their side during the instructions. The officer will have the subject raise one leg of their choosing straight out so that their foot is approximately 6 inches from the ground. When the test starts and the leg is raised, the subject will count 1000-1, 1000-2, 1000-3, and so on in that fashion. If the subject loses balance and puts their foot down, they are instructed to lift their leg back up as soon as possible and resume counting where they left off. The test lasts 30 seconds, so the final count should be 1000-30 or so.

Additional Tests to Look Out For

Apart from these three, there are a few other tests that are often offered during a DUI investigation.

  • Alphabet Test – the officer might ask the subject to recite all or a portion of the alphabet (e.g. D-T). Though the officer can ask you to recite a portion in the middle of the alphabet, they will not ask you to recite it backwards. That is a myth.
  • Counting – the officer might ask a person to recite a range of numbers starting with 1 or starting elsewhere. Unlike the Alphabet Test, the officer may ask the subject to recite the numbers counting up or counting down (e.g. 56-38).
  • Finger Dexterity Test – with this test, the officer will have the subject touch their thumb to each finger in order (index, middle, ring, pinky) and back (pinky, ring, middle, index) while counting (1, 2, 3, 4) and (4, 3, 2, 1). The officer may ask the subject to perform one or numerous “cycles” of this action. Although officers have been known to offer this test during DUI investigations, it actually only has scientific backing when offered in cases of Boating While Intoxicated. This is because the test has a direct relationship to the equilibrium in the inner ear, which can be affected by the combination of intoxication and being on a watercraft.

Preliminary Breath Test

The Preliminary Breath Test (PBT) is the last test that is offered to a subject of a DUI investigation. It is a roadside breathalyzer that may only be used for purposes of probable cause to justify a DUI arrest under Virginia law. As with all SFSTs, this test is completely voluntary and you may refuse to perform the roadside PBT.

Preparation and understanding what to expect is only the first step to protecting your rights. If you are pulled over for a DUI or are already facing DUI charges, make sure to contact the Fairfax Virginia DUI defense attorneys at Rudolphi Law to get the representation you can count on.