DUI and your commercial driver's license in South Carolina

Two sets of rules

A commercial driver arrested for DUI in South Carolina faces the same criminal case and the same DMV suspension as anyone else; the penalties guide and the DMV hearing guide cover those. On top of that, the South Carolina Commercial Driver License Act (S.C. Code § 56-1-2010 and following) adds a separate disqualification from driving commercial vehicles. Disqualification is the CDL word for losing the right to drive a commercial vehicle; your regular driving privilege is handled separately.

The act defines a commercial motor vehicle as one that has a gross vehicle weight rating of 26,001 pounds or more, is designed to carry 16 or more people including the driver, or is carrying hazardous materials that must be placarded.

The limits behind the wheel of a truck

Two rules apply only while you are driving a commercial vehicle (§ 56-1-2120):

• Any measurable alcohol. You may not drive a commercial vehicle with a measurable amount of alcohol in your body. If you do, or if you refuse a test, you must be placed out of service for 24 hours, meaning you cannot drive a commercial vehicle for that period.
• 0.04 or more. Driving a commercial vehicle with an alcohol concentration of 0.04 or more leads to disqualification under § 56-1-2110. That is half the 0.08 level that allows an inference of impairment in an ordinary DUI case.

The same section also bars being on duty or driving a commercial vehicle while possessing alcohol that is not part of the manifest and shipped as cargo.

What leads to disqualification

Under § 56-1-2110(A), you are disqualified from driving a commercial vehicle for at least one year after a first conviction for any of these:

• driving any motor vehicle under the influence of alcohol, a controlled substance, or an impairing drug, as defined by state law
• driving a commercial vehicle with an alcohol concentration of 0.04 or more
• refusing a test to determine alcohol concentration while driving a motor vehicle
• leaving the scene of an accident involving a vehicle you were driving
• using a motor vehicle in the commission of a felony
• driving a commercial vehicle while your CDL is revoked, suspended, or canceled, or while you are disqualified, because of earlier violations in a commercial vehicle
• causing a death through negligent operation of a commercial vehicle

The first item says "a motor vehicle," not "a commercial motor vehicle." A DUI conviction in your personal car counts.

How long it lasts

The law lets the DMV set rules under which a lifetime disqualification may be reduced to no less than ten years. Using a commercial vehicle in a felony involving the manufacture or distribution of controlled substances is a lifetime disqualification with no such reduction mentioned.

Because the list mixes offenses, a DUI conviction and a later refusal, or two DUIs years apart, can be enough for life. Only offenses committed after the act took effect count, but that was in 1989.

Refusing a test as a commercial driver

Anyone who drives a commercial vehicle in South Carolina is considered to have consented to a breath, blood, or urine test (§ 56-1-2130). An officer who has stopped you and has probable cause to believe you were driving a commercial vehicle with a measurable amount of alcohol can ask you to take one.

Before the test, the officer must warn you that refusing means:

• being placed out of service immediately for 24 hours, and
• being disqualified for at least one year under § 56-1-2110.

If you refuse, or test at 0.04 or more, the officer reports it to the DMV, and the DMV must disqualify you. This is in addition to the ordinary refusal suspension and the 30-day hearing window described in the refusal guide.

Employers, interlocks, and drug tests

• Employer vehicles. South Carolina's interlock law lets some people drive an employer's vehicle for work without an interlock under an employer's statement. The law says the statement covers the employer's noncommercial vehicles. It does not open a door to driving a truck. See the ignition interlock guide.
• Workplace testing. Employers must report to the DMV, within three business days, a commercial driver's refusal to give a specimen for a required drug or alcohol test, and testing officials report verified positive results (§ 56-1-2220). The DMV disqualifies the driver until a substance abuse professional's assessment and the recommended program are completed, which is separate from ADSAP.

Drivers from other states

If your CDL was issued by another state and you are convicted in South Carolina of a traffic offense other than parking in a commercial vehicle, the DMV must notify your home state's licensing agency within ten days (§ 56-1-2140). Your home state then applies its own CDL rules. The out-of-state guide covers the rest.

If you drive for a living and were just arrested

• Tell any lawyer you call that you hold a CDL, and whether you were in a commercial vehicle. The questions differ.
• Keep every notice you get from the officer and the DMV. The 30-day hearing deadline on a Notice of Suspension still applies.
• Ask your employer, or your own policy, what they require you to report and when. We could not confirm one rule that fits every employer, so read your company policy.
• Do not drive a commercial vehicle until you know whether you are out of service or disqualified.
• Talk to a South Carolina attorney; the DUI lawyer guide explains how to find one.

Penalties and procedures can change. Confirm the current rules with the DMV, the court, or an attorney before you rely on them.