A DUI law may prohibit driving under the influence of an alcoholic beverage, driving under the influence of a drug, and driving under the combined influence of an alcoholic beverage and any drug (legal or illegal), regardless of blood-alcohol level. To prove a person is guilty of the offense of driving under the influence, the following elements must be proven:
- The person drove a vehicle — that is, steered and controlled it while it was moving.
- At the same time, the person was “under the influence” in that his or her ability to drive safely was affected to an appreciable degree by having drunk an alcoholic beverage, taken a drug, or combined alcohol and drugs. (Note that some people’s driving can be impaired after having consumed even a relatively small amount of drugs or alcohol.)