California Driver's Handbook, Section 9: Alcohol and Drugs
California's DUI rules: legal blood alcohol limits, open containers, chemical tests, penalties, and the stricter rules for drivers under 21.
Summary written by MyPermitExam from the official handbook, DL 600 (REV. 6/2025). Not a copy of the handbook. Checked Oct 2026. Not affiliated with the DMV. California Driver's Handbook
Key rules
- DUI laws cover alcohol and any drug that affects your driving, including prescription and over-the-counter medicines. p. 72
- If an officer suspects DUI and you refuse a blood or urine test, DMV suspends or revokes your driving privilege for one year. p. 72
- Alcohol or cannabis in the car must be sealed and unopened; an open container goes in the trunk, never in the glove box. p. 72
- Legal BAC limits: 0.08% at 21 and older; 0.01% under 21 or on DUI probation; 0.04% for commercial drivers and when driving passengers for hire. p. 73
- Being under the limit does not mean it is safe to drive: you can be convicted of DUI even without a BAC measurement. p. 73
- A DUI conviction brings a one-year suspension or revocation, a DUI program, an SR 22/SR 1P insurance certificate, and possibly an ignition interlock device and up to six months in jail. p. 74
- DUI convictions stay on your driving record for 10 years. p. 74
- Under 21, you may carry alcohol only with someone 21 or older and in a full, sealed container. If caught with alcohol, your car can be impounded for up to 30 days. p. 75