Alcohol, Drugs, and Driving
What this domain covers
This domain tests impairment law and physiology: blood alcohol concentration (BAC) limits, how alcohol and drugs affect driving, implied consent, and the penalties for DUI in Delaware.
BAC limits
Delaware's per se limits are 0.08% for drivers 21 and older, 0.02% for drivers under 21 (zero tolerance), and 0.04% for commercial driver's license holders. Impairment begins well below 0.08: at 0.05 most drivers have reduced coordination, slower reaction time, and less peripheral vision, and they feel more confident than they are. Alcohol is a depressant, so it slows the brain and body. Only time removes alcohol; coffee, cold showers, and food do not sober you up.
Drugs, medications, and cannabis
DUI applies to any substance that impairs driving, including illegal drugs, cannabis, and prescription or over-the-counter medicines. Delaware allows adults 21 and older to possess limited cannabis, but driving under its influence is still illegal, and cannabis can impair judgment, reaction time, and lane control. Read medication labels; may cause drowsiness or do not operate machinery means do not drive. Mixing alcohol with drugs multiplies impairment.
Implied consent and penalties
By driving in Delaware you consent to a chemical test when lawfully arrested for DUI. Refusing is a separate violation: your license is revoked for at least a year for a first refusal, and the refusal can be used against you. A first DUI brings fines, license revocation, and mandatory alcohol education; repeat offenses bring jail time and ignition interlock. Open containers of alcohol in the passenger area of a vehicle are illegal.
Worked example
A 30-year-old driver is stopped for weaving, smells of alcohol, and fails field sobriety tests, but the breath test reads 0.05%. Can they be charged with DUI? Yes. The 0.08 figure is a per se limit, not the only way to prove DUI; the state can use driving behavior, physical signs, and field-test performance to show impairment. A driver under 21 at 0.05 would also be over the 0.02 zero-tolerance limit.
Traps
Thinking under 0.08 means safe; counting drinks instead of measuring time; assuming beer is weaker than liquor (a standard drink is the same); believing coffee or a shower sobers you; and refusing the test to avoid trouble - refusal carries its own revocation.