The arrest and trial for a DUI for drugs or alcohol doesn’t differ very much at all. The tests administered on the field are the same and the officer is going to testify regarding any types or signs of impairment that were present, which generally don’t differ much either. The type of test that determines the individual’s level of impairment is where the difference comes in. For alcohol, it will be the breathalyzer test, and for drugs, it will be the blood test.