Being “drunk” is very subjective. Individuals have different tolerance levels to alcohol depending on their height/weight, gender (female versus male) and other factors. Tolerance to alcohol at very high levels is also possible due to alcoholism. Many people don’t even think they’re “drunk” while driving.
The actual legal standard in DUI cases is whether you were operating a motor vehicle safely under the circumstances. If you are under the influence of alcohol, drugs (even prescription medications) or combination of both, you can be charged with a DUI.
In California, if your blood, breath or urine test reveals a blood alcohol content (BAC) of .08 or higher, you are presumed to be under the influence. You can then be charged with two offenses:
1) Vehicle Code section 23152(b), Driving with a Blood Alcohol Level of .08 or Higher;
2) Vehicle Code section 23152(a), which means that even if your test result is less than the .08 legal limit you can still be charged with a DUI. Reasons include bad or erratic driving, failing Field Sobriety Tests (FST’s), the police officer’s observations of anything from alcohol on your breath, slurred speech, unsteady gait, etc. after you are pulled over.