In Massachusetts you will be convicted of operating under the influence (OUI) if you have a blood alcohol concentration of .08% or greater. An OUI is an interchangeable term with DUI (driving under the influence) that are both crimes committed by operating a vehicle while intoxicated or under the influence of drugs. Legal limit in Massachusetts: Standard, non-commercial drivers: .08% BAC  Commercial drivers: .04% BAC Drivers under 21: .02% BAC Penalties, Fines, & Suspension Massachusetts OUI & DUI Penalties, Fines, & Suspension Penalty 1st offense