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What are some initial things an officer will look at to stop a vehicle for a DUI?

Before a DUI suspect is asked to take a PAS test (Preliminary Alcohol Screening); perform Field Sobriety Tests (FSTs); and provide a sample of his or blood, breath, or urine to determine their Blood Alcohol Concentration (BAC), an arresting officer must first stop the vehicle.

When arresting officers stop a vehicle, he or she must have sufficient evidence to suspect that someone is driving under the influence of alcohol or drugs. Therefore, the operation of a motor vehicle is the first action a law enforcement officer will look at to make this determination.

Officers are expected to mentally record, with enough accuracy, the normal actions expected of a driver, in addition to the abnormal actions or behaviors, which might indicate that someone is driving under the influence of alcohol or drugs.

When a driver operates a vehicle in any manner that would raise a doubt as to his or her sobriety, or other abnormal conditions, an officer will likely conduct a stop of the vehicle to determine the cause of the irregular, abnormal, or unusual driving.

When gathering evidence to determine if a stop will be made for suspected DUI, officers will look at certain cues:

  • A moving traffic violation or equipment violation.
  • Driving actions that are unusual – for example, weaving within a lane, across lanes, or driving at a very slow speed.
  • If the driver was involved in traffic accident or collision.
  • Statements made from a witness about the suspect's driving.
  • The suspect driving into a DUI checkpoint.

This list is not exhaustive and it should be emphasized that a prolonged observation of certain cues is not necessary. What is necessary is reasonable suspicion; that is, an officer must have specific facts (not a hunch) that can be articulated to justify the stop.

If you have been arrested, charged, or are under investigation for DUI, contact my office today. I will provide a free, confidential consultation.