Louisiana has strict drinking and driving laws to protect its roads. You can be convicted of a DWI or driving while impaired if you are caught driving with a BAC (blood alcohol concentration) of .08% or higher. Penalties and punishments vary based on degree of BAC levels, multiple offense and other factors. Legal limit in Louisiana: Standard, non-commercial drivers: 0.08% BAC Commercial drivers: 0.04% BAC Drivers under 21: 0.02% BAC Penalties, Fines, & Suspension Louisiana DUI & DWI Penalties, Fines, & Suspension Penalty 1st offense