Police officers look for specific signs that a driver is under the influence of alcohol, but not all of these occur after the vehicle has been stopped. Sometimes, officers spot things that indicate that a driver might not be able to drive safely, so they will initiate a traffic stop. This enables them to evaluate the driver to determine what is going on.

To pull a vehicle over, the officer only needs to have reasonable suspicion that the driver is impaired, which means they only think that it is possible based on observations. This is a much lower standard than probable cause, so even small signs of a problem can lead to the stop. Probable cause means the officer has evidence that suggests a person committed a crime.

What actions constitute reasonable suspicion?

Many things can make it appear as though a driver is intoxicated, but these aren’t definitive indications. It is possible that they are signals of other conditions or problems that aren’t related to alcohol or drugs. Some of the common signs police officers look for include:

  • Suddenly braking in traffic lanes for no reason
  • Swerving between lanes
  • Braking frequently even without fully stopping
  • Making illegal turns
  • Almost hitting things on the side of the road
  • Driving too slow or too fast for current conditions
  • Operating the vehicle erratically

What happens when the car is stopped?

The officer will attempt to determine if the driver is intoxicated. Initial clues often include the smell of alcohol on the driver’s breath, open containers in the vehicle or bloodshot eyes. This might be done by having the person do a field sobriety test. If this indicates that the person is impaired, the officer will ask them to take a chemical test to determine the person’s blood alcohol concentration percentage.

Drivers who have a BAC of .08% or higher are arrested. Even with a lower BAC, it is possible to face criminal charges if you are showing signs of impairment that make it unsafe to drive. In some cases, this is because of drugs that have similar effects to alcohol.

Defendants in drunk driving cases must learn their defense options immediately. Building a defense requires you to look at the circumstances and decide the method of addressing the prosecution’s claims. This enables you to consider the impacts that they will have on your life now and in the future.