In Colorado, there are four basic alcohol-related traffic offenses that may be charged:  Driving Under the Influence (DUI), Driving While Ability Impaired (DWAI), Driving With Excessive Alcohol Content (DUI Per Se), and Underage Drinking and Driving (UDD or “Baby DUI”).  The definitions of DUI and DWAI include drugs, while the definitions of DUI Per Se and UDD are limited to alcohol.  The offenses of DUI, DUI Per Se and DWAI are traffic misdemeanors; while UDD is a Class A traffic infraction. 

         DUI is defined as driving a vehicle when a person has consumed alcohol or drugs or a combination of alcohol and drugs which affect the person to a degree that the person is substantially incapable, either mentally or physically, or both mentally and physically, to exercise clear judgment, sufficient physical control, or due care in the safe operation of a vehicle.  DWAI is defined as driving a vehicle when a person has consumed alcohol or drugs or a combination of alcohol and drugs, which affect the person to the slightest degree so that the person is less able than the person ordinarily would have been, either mentally or physically, or both mentally and physically, to exercise clear judgment, sufficient physical control, or due care in the safe operation of a motor vehicle.  DUI Per Se is defined as driving a vehicle when the person’s BAC is .08 or more at the time of driving or within two hours after driving.  Consuming alcohol during that time period can be considered an affirmative defense.  UDD is charged when a person under twenty-one years of age drives a vehicle in this state when the person’s BAC is at least .02 but not more than .05 at the time of driving or within two hours of driving.