DWI and Your Commercial Driver's License (CDL) in Minnesota

The Bottom Line: CDL Disqualification

This is the consequence that matters most. Under Minnesota law (Minn. Stat. § 171.165) and the federal rules that all states must follow, a "major offense" triggers a mandatory CDL disqualification:

• One year for a first major offense — including a DWI, refusing a chemical test, or operating a commercial vehicle at 0.04% or more;
• Three years if you were transporting hazardous materials at the time;
• Lifetime for a second major offense (a lifetime disqualification may be reduced to a minimum of 10 years if you complete an appropriate rehabilitation program).

And critically: there is no work permit or temporary commercial driving privilege during a disqualification. Unlike a regular license, where a limited "work permit" may sometimes be available, a disqualified CDL means no commercial driving — period — for the full disqualification.

A Lower Limit: 0.04% in a Commercial Vehicle

While the ordinary DWI limit is 0.08%, a commercial driver operating a commercial motor vehicle is over the limit at 0.04% — half the standard. There are also strict on-duty rules: a commercial driver generally may not consume alcohol while on duty or within four hours before going on duty.

What Counts as a "Commercial Motor Vehicle"

A commercial motor vehicle (CMV) is generally a vehicle (or combination) used to transport passengers or property that meets certain thresholds, including:

• Heavier weight ratings (for example, combinations over 26,000 pounds with a heavy towed unit);
• Vehicles designed to carry a larger number of passengers;
• Vehicles transporting hazardous materials requiring placarding; and
• Most school buses (other than small "type III" buses).

Minnesota issues a single driver's license with classes and endorsements (Classes A through D), and you need the proper class and endorsement to operate things like buses, tank vehicles, multi-trailer combinations, or hazardous-materials loads.

The Personal-Vehicle Trap

Years ago, Minnesota law protected commercial driving privileges by issuing a limited license that let a CDL holder keep driving commercially even after a DWI in their personal vehicle. That exception is gone. Since the mid-1990s, a commercial driver who gets a DWI in a personal passenger vehicle receives no special exemption — the disqualification applies the same as it would for any disqualifying offense. Federal law reinforces this: a DWI in any vehicle triggers the CDL disqualification.

Refusing a Test Has the Same Effect

For CDL purposes, refusing a chemical test is treated as a major offense just like a DWI conviction — it carries the same one-year (or longer) disqualification. So "just refusing" is not a way to protect a CDL.

School Bus Drivers: Two Laws at Once

School bus and Head Start bus drivers face overlapping rules. They're subject to a separate zero-tolerance standard, but the regular DWI law also applies if their alcohol concentration is 0.04% or more (or 0.08% or more for a small "type III" bus). A driver caught at those levels could be charged under both the school bus law and ordinary DWI law — and face the penalties of both.

Two Separate Battles

A commercial driver facing a DWI is really fighting on multiple fronts at once:

• The criminal DWI case (and any test-refusal charge);
• The regular license revocation (implied consent); and
• The CDL disqualification — the one most likely to end a career.

What this means for you: Because the CDL consequence is so severe and is driven by the underlying DWI/refusal outcome, how the criminal and implied-consent matters are handled can directly affect whether you keep your commercial license. There are short deadlines to challenge the administrative actions, so getting advice quickly is essential. Anyone facing CDL disqualification also has the right to administrative review and may petition the district court regarding reinstatement.

Key Terms

• CDL disqualification: The loss of commercial driving privileges — 1 year / 3 years (hazmat) / lifetime.
• 0.04% limit: The lower alcohol-concentration limit for operating a commercial motor vehicle.
• Major offense: A DWI, test refusal, or 0.04%+ in a CMV — each triggering disqualification.
• Commercial motor vehicle (CMV): A vehicle meeting weight, passenger, or hazmat thresholds.
• No work permit: Unlike a regular license, no temporary commercial driving is allowed during disqualification.