Drunk Driving Terminology - DUI, DWI, BAC, and Related Terms

By Nicole Sauvola

Sauvola & Associates, P.A.

Updated:  June 2007

Contents

• Offense Terms
• Testing Device / Breathalyzer Terms
• Field Sobriety Tests
• Additional Terms

Notice: Please note that if you have been charged with a drunk driving offense, you will benefit from consulting a criminal defense lawyer. For information about what you should do after an arrest for drunk driving, please contact our office at (561)515-6118. If you wish to hire a defense lawyer, you may find this article on "Choosing A Lawyer" to be helpful.

Commonly used terms in drunk and impaired driving cases include:

Offenses:

• DWI - Driving While Impaired
• DUI - Driving Under the Influence
• OMVI - Operating a Motor Vehicle while Impaired
• OUI - Operating Under the Influence
• OUID - Operating Under the Influence of Drugs
• OUIL - Operating Under the Influence of Liquor
• OWI - Operating While Impaired
• "Per Se" Offense - A drunk driving offense which can result in conviction based upon proof of breath/blood alcohol content (BAC), without any proof of impairment of ability to drive.
• UBAL - Unlawful Breath/Blood Alcohol Level

Testing Devices ("Breathalyzer" Tests)

• BAC Datamaster - A breath analysis device which produces an estimate of blood alcohol based upon infrared spectroscopy. These devices are designed to be low-maintenance, and relatively easy to use. However, they are not foolproof, and mistakes may occur in calibration, maintenance and storage, operation and use of the devices. A BAC device may also detect presence of chemicals other than alcohol, for example detecting acetone in the breath of diabetics.
• Breathalyzer - (This is the Instrument/Machine used in Florida) A breath analysis device which produces an estimate of breath alcohol based upon the chemical analysis of a breath sample. Many states have phased out these devices, due to new technologies which are less difficult to administer and less prone to error. However, due to their wide use, many people refer to any breath testing device as a "breathalyzer".
• Intoxylizer - A breath analysis device which produces an estimate of blood alcohol based upon infrared spectroscopy.
• Intoximeter - Intoximeter devices are based upon fuel cell technology, infrared spectroscopy, or a combination thereof. Fuel cell technology involves the chemical analysis of a breath sample, to create a measurable electrical reaction which provides a measure of breath alcohol concentration. Early models of this device were susceptible to error from radio frequency interference.
• PBT - Preliminary Breath Test - A PBT device is portable in nature, and is often carried by police in the field. PBT devices provide an estimate of blood alcohol concentration. However, due to the nature of the devices and the circumstances under which they are used, PBT results are not ordinarily admissible in court except under unusual circumstances.

Field Sobriety Tasks/Exercises

Field or Roadside Sobriety Tasks/Exercises are used to establish probable cause for administration of a preliminary breath test, or for a drunk driving arrest and administration of a formal breath or blood test.

• The Standardized Field Sobriety Task (SFST) is a battery of three tasks administered and evaluated in a standardized manner to obtain validated indicators of impairment and establish probable cause for arrest. The tasks administered under this protocol are the horizontal gaze nystagmus test, the walk-and-turn task, and the one-leg stand.
• Divided Attention Tasks - Tasks which require a suspect to listen to and follow instructions while performing simple physical movements. Such tasks administered in Florida include, but are not limited to the walk-and-turn task, one-leg stand task, the finger-to-nose task, and the rhomberg alphabet task.

Commonly administered sobriety tests include:

• Counting - The suspect is asked to count forwards or backwards, usually by ones or threes. Signs of impairment include (1) skipping letters, (2) loss of concentration, and (3) slurred speech. This is not a particularly accurate or reliable sobriety test.
• Finger to Nose - The suspect stands, usually with the head tilted back and eyes closed, with arms stretched out to his sides. The suspect then attempts to touch the tip of his index finger to his nose, first with one arm and then the other. Signs of impairment include (1) beginning before instructions are completed, (2) swaying or staggering, (3) using arms to balance, (4) losing balance, and (5) inability to touch fingertip to nose. This test can be difficult to perform even when sober, without practice.
• Reciting the Alphabet - The suspect is asked to recite the alphabet, sometimes backwards. Signs of impairment include (1) skipping letters, (2) loss of concentration, and (3) slurred speech. This test is not particularly accurate, and may not be appropriate for suspects for whom English is not the primary language.
• Standing on One Leg - The suspect is instructed to stand on one leg, with the other foot suspended approximately six inches off the ground and count aloud by thousands ("One thousand-one", "one thousand-two", etc.) until instructed to put the foot down. The officer times the suspect for thirty seconds. The officer looks for indicators of impairment, including (1) swaying while balancing, (2) using arms to balance, (3) hopping to maintain balance, (4) not counting in order, and (5) putting the foot down.
• Walking a Line - A suspect is asked to walk a straight line. This should occur on a flat, even surface, at a safe distance from traffic. The officer looks for signs of impairment including (1) beginning before instructions are completed, (2) swaying or staggering, (3) using arms to balance, and (4) stopping walking to regain balance.
• Walk-and-Turn - A suspect is instructed to take nine steps along a straigt line, walking heel-to-toe. After taking the steps, the suspect must turn on one foot and return in the same manner in the opposite direction. The examiner looks for seven indicators of impairment: (1) if the suspect cannot keep balance while listening to the instructions, (2) begins before the instructions are finished, (3) stops while walking to regain balance, (4) does not touch heel-to-toe, (5) uses arms to balance, (6) loses balance while turning, or (7) takes an incorrect number of steps.
• Horizontal Gaze Nystagmus - Horizontal gaze nystagmus is an involuntary jerking of the eyeball which occurs naturally as the eyes gaze to the side. This test theorizes that when a person is impaired by alcohol, nystagmus is exaggerated, and that alcohol-impaired person will have difficulty smoothly tracking a moving object. To administer this test, an officer asks the suspect to watch a slowly moving object, such as a pen or small flashlight. As the officer moves the object horizontally (back and forth), the officer watches the suspect's eyes as they follow the object, watching for signs that (1) the eye cannot smoothly follow a moving object, (2) distinct jerking when the eye is at maximum deviation, and (c) an angle of onset of jerking within 45 degrees of center. The presence of four or more signs between a suspect's two eyes is considered to suggest unlawful intoxication. The circumstances of a roadside administration, or a lack of training for the officer administering the test, can significantly affect test results.

Additional Terms:

• Administrative Penalty - A sanction which may be imposed through an administrative agency, such as a state department of motor vehicles (DMV), even without criminal prosecution.  It is important to note that there is a 10-day window within which to request an Administrative Hearing for the return of your driver's license after you have been stopped, arrested and charged with DUI in Florida.  You must contact an attorney immediately in order to prevent the loss of the right to this hearing.
• BAC - Breath/Blood Alcohol Content, usually expressed in a number reflecting the ratio of milligrams of alcohol in 100 milliliters of breath/blood.
• BAL - Blood Alcohol Level. The same as Blood Alcohol Content.

Copyright © 2006  Nicole Sauvola. All rights reserved. No portion of this article may be reproduced without the express written permission of the copyright holder, except as follows: You may link this article to your website, either directly or through an index page, provided your link does not depict this article, its author, or Sauvolaw.com in a negative manner.