In Kentucky, a person can be arrested for a DUI if their blood alcohol concentration (BAC) is .08% or higher. A DUI, or driving under the influence, is a drunk driving conviction where the BAC is above the state legal alcohol limit, rendering the driver legally impaired. Legal limit in Kentucky: Standard, non-commercial drivers: 0.08% BAC Commercial drivers: 0.04% BAC Drivers under 21: 0.02% BAC Penalties, Fines, & Suspension Kentucky DUI & DWI Penalties, Fines, & Suspension Penalty 1st offense 2nd offense 3rd offense Sentence