A police officer that suspects an individual is driving under the influence (DUI) of alcohol must have a "reasonable suspicion" that a driver has been drinking. This simply means a police officer must have observed something in an individual’s driving or conduct that might indicate he or she is under the influence of alcohol. 

While DUI laws vary from state to state, most states will require the following elements to be present for a DUI to apply:

  1. The driver is operating a vehicle; and
  2. The driver is intoxicated.

What Constitutes a DUI Arrest?

A DUI arrest usually occurs after the officer has stopped the driver for a traffic violation and after the stop the officer has probable cause to believe that the driver is under the influence of alcohol or drugs or is otherwise too impaired to drive a motor vehicle safely. After the stop has been made and the officer has conducted a field sobriety test, the first stage of the criminal process in a DUI case begins once the officer has placed the driver under arrest.

When Can an Officer Make a DUI Arrest?

A police officer that has stopped a vehicle for a traffic violation may place the driver under arrest for a DUI in the following circumstances:

  • Police Officer Has Probable Cause: If the police officer personally sees or believes that the driver has committed a crime, the officer may lawfully arrest that person. For example, if the police officer believes that driver is driving under the influence because the driver smells like alcohol or officer notices empty beer bottles in his vehicle, the officer may arrest the driver based on probable cause that the driver has been driving under the influence.
  • Police Officer Made a Lawful Traffic Stop: The officer had probable cause to believe that the driver is under the influence. Officer must show that he or she did not stop the vehicle randomly or for no reason. There must be proof that the driver did something in violation of a law, which led to the traffic stop.
  • Police Officer Has an Arrest Warrant: The officer can place the driver under the arrest after the traffic stop if the officer had a valid arrest warrant issued by a judge or magistrate.

What If the Driver Has Not Had Any Drinks?

A person that is pulled over by a police officer under suspicion of driving while intoxicated should comply with police officers requests. Some states require field sobriety tests. Passing the tests will likely mean an individual can safely drive away without any further difficulty. However, these tests are highly subjective and it is possible for someone who has not been drinking to still fail.

What If the Driver Does Not Pass Sobriety Tests?

An individual that hasn’t been drinking but has been instructed by a police officer that they haven’t adequately passed a field sobriety test should comply with the officer’s demands. Generally, a police officer will take a person into custody and will be booked.

Now that many states have legalized marijuana, it is possible to be charged with a DUI if you smoke/imbibe cannabis and drive. In fact, it is also possible to be charged with a DUI if you’ve taken strong prescription drugs. It’s important to keep in mind that any substance that can alter your ability to drive, whether obtained legally or illegally, can result in a DUI. Not just alcohol!

Should I Consult an Attorney?

An individual that has been arrested should contact a local DUI/DWI lawyer. They can help to evaluate any evidence of law enforcement officials and determine the credibility of each piece of evidence.