In many states it is a criminal offense (DUI/DWI) to operate a commercial vehicle with a blood alcohol concentration of .04 or more—which is half of the BAC usually required to commit the DUI/DWI offense while driving a non-commercial vehicle. Because most holders of commercial driver’s licenses (CDLs) depend on their license to earn a living, the consequences of a DUI/DWI conviction for a CDL holder—including a conviction while operating a non-commercial vehicle—are serious.

Laws vary from state to state but a CDL holder’s license may be suspended for one year for the first offense, and with a second DUI/DWI conviction the CDL holder may be permanently disqualified from holding a CDL.

These laws are generally located in a state’s statutes—often in the vehicle code, motor vehicle code, or transportation code.

In Delaware, it is indeed a criminal offense for a commercial vehicle operator to have a blood alcohol concentration (BAC) of .04 or higher, which is stricter than the .08 BAC limit for non-commercial drivers. This is in accordance with federal regulations that apply to all states. For CDL holders in Delaware, the consequences of a DUI/DWI are severe and can significantly impact their livelihood. Upon a first DUI/DWI offense, a CDL holder faces a one-year suspension of their commercial driver's license. If the offense involves transporting hazardous materials, the suspension period extends to three years. A second DUI/DWI conviction results in a lifetime disqualification from holding a CDL, which can be reduced to 10 years upon meeting certain conditions. These regulations are designed to promote safety on the roads and ensure that commercial vehicle operators adhere to strict standards of sobriety. The specific laws governing DUI/DWI offenses for CDL holders in Delaware can be found in the state's transportation code or vehicle code.