Reasonable suspicion, probable cause and your DUI stop

In Georgia, it is against the law to drive under the influence of alcohol. Consequently, if you have a blood alcohol concentration above 0.08% and have physical control of a motor vehicle, you are vulnerable to arrest and prosecution.

Before officers can legally stop your vehicle, they typically must have reasonable suspicion you are breaking the law. To arrest you, though, they must also have probable cause. If officers lack either of these, any evidence they obtain during your DUI stop may be inadmissible in court.

Reasonable suspicion

The Fourth Amendment to the U.S. Constitution protects you from unreasonable searches and seizures. Because a DUI stop is a type of search, officers must act reasonably when detaining you. The following likely gives officers reasonable suspicion to stop your vehicle:

  • Swerving or changing lanes erratically
  • Speeding or driving below the speed limit
  • Unpredictable braking or accelerating
  • Traffic accidents or near misses

Probable cause

While reasonable suspicion is enough for a DUI stop, officers likely need probable cause to search you or your vehicle. If officers want to arrest you for a DUI offense, they also need probable cause. Failing a field sobriety or breath test is likely to give officers sufficient probable cause to support your DUI arrest.

Sobriety checkpoints

Georgia law allows law enforcement agencies to erect sobriety checkpoints. At these roadblocks, officers stop all approaching vehicles or a random sample of them. Provided officers comply with strict legal requirements, they do not need reasonable suspicion to stop a vehicle at a DUI roadblock.