DUI Investigations
Fort Lauderdale DUI Attorney | Miami DUI Attorney
Phase I DUI Investigations | Vehicle in Motion
Police officer’s are trained to follow the guidelines set forth by the National Transportation and Safety Administration(NHTSA) when conducting a DUI investigation. The guidelines set forth 3 stages to every DUI arrest. The officers are trained to identify “cues” of impairment in each stage of the investigation. The cues are used to develop probable cause to support a traffic stop and an arrest.
Phase I, Vehicle In Motion Phase I of a DUI investigation is broken down into three subparts. It consists of a) the observation of the vehicle while it is being driven; b) the decision to make a traffic stop; and c) observations made during the traffic stop. The initial observation of the vehicle begins when the officer, for whatever reason, notices the vehicle. The officer may have witnessed the driver commit a traffic infraction or just thought “Hey! Nice car!” The reason why the officer notices the vehicle is not relevant.
Once the officer notices the vehicle, the officer is trained to look for 24 specific cues that NHTSA has determined to have a statistically significant correlation to impairment. The correlation of the cues range from .35 to .90. Accordingly, one indication of impairment is not going to be probable cause for a DUI stop. The probability that an individual is impaired increases with the number of cues exhibited by the driver. Typically, officers are looking for two or more cues. It is important to realize that any traffic infraction can be used as a basis to stop a vehicle even if the infraction is not a specifically listed cue.
NHTSA has divided the driving behaviors into four categories:
- Problems in maintaining proper lane position | Statistical Correlation to Impairment .50- .75
Weaving Weaving across lane lines Straddling a lane line Swerving Turning with a wide radius Drifting Almost striking a vehicle or other object
- Speed and braking problems | Statistical Correlation to Impairment .45 – .70
Stopping problems (too far, too short, or too jerky) Accelerating or decelerating for no apparent reason Varying speed Slow speed (10+ mph under limit)
- Vigilance problems | Statistical Correlation to Impairment .55 – .65
Driving in opposing lanes or wrong way on one way Slow response to traffic signals Slow or failure to respond to officer’s signals Stopping in lane for no apparent reason Driving without headlights at night Failure to signal or signal inconsistent with action
- Judgment problems. Statistical Correlation to Impairment .35 – .95
Following too closely Improper or unsafe lane change Illegal or improper turn Driving on other than designated roadway Stopping inappropriately in response to officer Inappropriate or unusual behavior (throwing objects, arguing, etc.) Appearing to be impaired
It should be noted that many times an individual is stopped for excessive speed and nothing more. Excessive speed is NOT an indication of impairment. However, varying speed and slow speed are indications. Special attention should be paid to the police report to see which cues listed by the officer are statistically correlated. Quite often, there are no statistically significant cues. While it will not usually not win a motion to suppress based on the stop, if the officer also witnessed a traffic violation, it is nice to be able to highlight to the jury that there were no indications of impairment based on the driving pattern.
In trial, or in a hearing, the prosecution tends to point to 2 or 3 cues of impairment to establish that a person was too impaired to drive. A good defense strategy is to focus on the 21 or 22 things that the defendant did correctly. A cross examination focusing on what the defendant did right is an extremely effective strategy when there is a “double refusal” meaning that the defendant did not take the roadside sobriety exercises and the defendant did not take a breath, blood or urine test.
When selecting a DUI attorney, ask the attorney about his or her additional training and education with regard to the NHTSA Standardized Sobriety Tests and the 3 Phases of a DUI arrest. The NHTSA Student Manual is available to attorneys and all serious DUI attorneys should have one.
For additional information, please contact
The Law Offices of Michael A. Dye, PA, 1 E Broward Blvd #700, Fort Lauderdale, FL 33301 (954)990-0525 or
The Law Offices of Michael A. Dye, PA, 2 S Biscayne Blvd, Miami, FL 33131 (305)459-3286
