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Field Testing

Walking a straight line or touching the tip of your finger to your nose are examples of field testing. A field test is a poor method of determining intoxication. The driver is nervous, perhaps tired, the roadway may be dark and poorly lit or the instructions are unclear. The officer's opinion that a driver is intoxicated on the basis of a roadside test can be overcome in court through cross-examination. The goal is to get the officer to admit he had no knowledge that the driver:

had a medical condition that makes her unsteady
  • had been driving for a long period of time
  • was tired or sleepy
  • suffered from allergies or some condition that affects her eyesight
  • If it was dark, rainy or the middle of the night, for example, get the officer to admit these facts as well, as they tend to show he may not have accurately seen the driver perform the field test. Through these admissions, it is possible to plant a reasonable doubt as to intoxication in the minds of the judge or jury.

    TIP: In some jurisdictions, you might refuse to participate in a field test, including a hand-held breath test, based on your rights against self-incrimination. There is no reason to consent; if the officer is determined to arrest you, you will be forced to give a blood test at some point anyway. By refusing, at trial the state will not have the officer's testimony that you "flunked" a field test.

    Do I have to consent to a field sobriety test (FST)?

    No. The results of the FST are subjective and only provide the state with more evidence against you. Your license cannot be suspended because of your refusal to take a FST; however, it is probable you will be arrested.

    What happens if I refuse to consent to testing?

    In addition to suspension or revocation of the driver's license, in some states, the penalties for refusal to alcohol testing are identical to a DUI conviction. Expect the police to confiscate your license at the police station. You may or may not be entitled to a hearing at a later time to determine if the suspension or revocation was proper.

    SIDEBAR: As soon as possible, write down:

    • the time and place of the last place you ate
    • what you ate
    • the time and place you first had a drink the day of the DUI
    • what type of drink and how many
    • the time and place you drank your last drink
    • the names of anyone that was with you

    Is failing an FST enough to permit an officer to arrest me?

    Yes. The failure, in and of itself, gives the officer probable cause to arrest you. In fact, failing to pass an FST along with the officer's observations of impairment is enough to convict you of a DUI, although chemical tests may be negative for alcohol content. In all probability, the prosecutor will dismiss the charge if the chemical test is negative, but you still are left with an arrest record.

    SIDEBAR: Some citizens have been successful in claiming false arrest and malicious prosecution where breath, urine and blood test were negative for alcohol, yet they were arrested based on a failed FST.

    Can I get a copy of the videotape from the police officer's patrol car?

    Most traffic stops and jail premises are videotaped. If you are contesting a DUI, the videotape can be your best evidence that you were not impaired. Rather than the officer's testimony, which will be colorful (e.g., indicating that you had slurred speech, bloodshot eyes, disheveled appearance and were uncooperative) and perhaps exaggerated, videotape shows your actual demeanor. Always ask if a videotape exists and get a copy.

    Can I be convicted of a DUI if there is no videotape that shows my alleged impairment?

    Yes. The testimony of the arresting officer, witnesses and physical evidence at the scene (opened beer can in the car, for example) are sufficient to convict you. A videotape is not required to convict a person of a DUI offense.

    Is the police officer's testimony at my trial that I was impaired relevant if the videotape made at the station shows that I am sober?

    Yes. You can be convicted on her testimony alone. If no videotape was made at the scene, a tape of you at a later time appearing sober will not defeat the officer's testimony.

    The videotape made when I was pulled over for a DUI does not show any impairment on my part at all. Can I still be convicted?

    Yes. The videotape is only some evidence of your sobriety. The police officer and witness can testify as to what they observed (erratic driving, smell of alcohol, etc.) Additionally, any traffic offenses you committed (running a red light, unlawful U-turn) will be used to prove you were impaired.

    SIDEBAR: Many states have a policy of videotaping the driver at the blood alcohol-testing site.