California Vehicle Code 23600 VC prohibits people on DUI probation from driving with any measurable amount of alcohol in their system. This is referred to as California's zero-tolerance law. People caught violating this law (or refusing to submit to a chemical test while on probation) can have their probation revoked. This will occur if the defendant's BAC is measured at 0.04% or greater. The defendant can usually avoid having probation revoked, however, by spending at least 48 hours in county jail. A more serious consequence of violating California's zero-tolerance law is an automatic one-year driver's license suspension. To fight this suspension, the defendant must request a DMV hearing within ten (10) days of the zero-tolerance arrest and then win it.