Alcohol and drugs
You are 19 years old. At what blood alcohol concentration (BAC) does it become illegal for you to drive in California?
- 0.01% or higher. Correct answer
- 0.05% or higher.
- 0.08% or higher.
Why
California applies a zero-tolerance standard to drivers under 21: a BAC of 0.01% or higher is illegal. The 0.08% limit is the one for drivers over 21, and lower limits apply to commercial drivers and drivers carrying passengers for hire (0.04%) and to anyone on DUI probation (0.01% at any age). The 0.05% figure has a real meaning for under-21 drivers, but it is not a limit: a preliminary alcohol screening at 0.05% or more lets the officer demand a breath or blood test, and when that later test reads the same figure, a DUI arrest and the loss of the driving privilege are both on the table. A DUI conviction under 21 lets DMV revoke the driving privilege for a year and requires completing a licensed DUI program, and refusing a chemical test costs the driving privilege for a year on its own.
Where this comes from
California Driver's Handbook, DL 600 ENGLISH (REV. 6/2025). The correct answer is 0.01% or higher..