Most regular readers of our Arizona DUI Defense Blog understand that it is illegal to drive a vehicle in our state with a blood alcohol concentration (BAC) of .08 percent or above. Doing so can result in a DUI arrest and drunk driving conviction.

However, fewer know that Arizona drivers can be charged with DUI if they are under the influence of liquor or any drug – or combination of alcohol and drugs – if they are “impaired to the slightest degree.”

The most common type of DUI charge involves a driver over 21 years old who is accused of driving with a BAC of .08 percent or above. There are also more serious drunk driving charges in cases in which a police officer believes you have a BAC of .15 percent or higher (Extreme DUI) and the Aggravated DUI category, which involves cases with certain aggravating factors, including:

  • The third DUI within seven years
  • Causing injury or property damage with driving drunk
  • DUI on a suspended or revoked driver’s license
  • Driving drunk with a passenger under 15 in the vehicle

Then there is Arizona law §28-1381(a)(1), which states that if you drive or are in control of a vehicle while “impaired to the slightest degree,” you, too, can be charged. Because Arizona is a zero-tolerance state, the “slightest degree” standard is problematic. There is no statutory definition for what that means, so it is often left to the discretion of the Prosecutor as to whether to charge it and then to the jury as to whether it was found. The unfortunate truth is that it can mean one thing to one person and something else to another.

It can be difficult for a prosecutor to prove to a court that you were objectively impaired on the basis of such a subjective assessment. Talk to a skilled DUI defense attorney about effective defenses that can protect your freedom and license in these matters.