Alcohol and drugs
You are 40 years old and on DUI probation. At what blood alcohol concentration (BAC) does it become illegal for you to drive?
- 0.01% or higher. Correct answer
- 0.08% or higher.
- 0.04% or higher.
Why
DUI probation puts you on the strictest line in the handbook and your age does not soften it: 0.01% or higher, at any age. That is the same figure the handbook sets for drivers under 21, so while you are on probation the ordinary adult allowance simply does not apply to you. The 0.08% answer is that ordinary adult limit, and 0.04% is the one for a vehicle requiring a commercial driver's license or for driving a passenger for hire. All DUI convictions remain on your driver record for 10 years, and if you pick up another DUI during that time the court or DMV may add a penalty on top.
Where this comes from
California Driver's Handbook, DL 600 ENGLISH (REV. 6/2025). The correct answer is 0.01% or higher..