DUI Laws in South Dakota: Penalties, BAC Limits & License Suspension

What a DUI Is Called in South Dakota, and the Numbers That Matter Right Now

South Dakota calls this offense Driving Under the Influence (DUI) — sometimes written in the statute as "driving or control of a vehicle while under the influence of alcohol, drugs, or an intoxicant" (SDCL 32-23-1). If you were arrested, three things matter immediately:

• Per se BAC limit: 0.08% for a standard driver's license, 0.04% for commercial drivers, and 0.02% for anyone under 21 (a near-zero-tolerance rule).
• Refusal penalty: refusing the chemical test triggers an automatic one-year license revocation for a first refusal, separate from and in addition to any DUI conviction.
• Hearing deadline: if you want to contest that revocation, South Dakota law gives you 120 days from the date of arrest to request a hearing with the South Dakota Department of Public Safety (DPS). That sounds like a long time compared to some states, but the request has to actually get filed — nothing happens automatically in your favor, and if you never ask, the revocation simply stands.

South Dakota's DUI law changes periodically, and county-level practice (bond conditions, 24/7 Sobriety Program enrollment, prosecutor charging decisions) varies. Everything below reflects South Dakota Codified Law (SDCL) Chapter 32-23 as currently published by the South Dakota Legislature; confirm current details with the DPS or a South Dakota criminal defense attorney before relying on any specific number for your case.

BAC Limits: Standard, Commercial, Under-21, and the High-BAC Threshold

Under SDCL 32-23-1, it's illegal to drive with a blood alcohol concentration of 0.08% or more — this is the "per se" limit that applies nationwide, not just in South Dakota. A driver can be convicted on the test result alone, without separate proof of impaired driving.

• Commercial drivers (CDL): 0.04%, consistent with federal commercial-vehicle rules.
• Drivers under 21: 0.02% (SDCL 32-23-21) — South Dakota's zero-tolerance law for minors. A BAC as low as one drink can trigger a charge, and any detectable marijuana or unprescribed controlled substance in the body counts too.
• High-BAC / "aggravated" threshold: South Dakota treats a BAC of 0.17% or higher as an aggravating factor at every offense level. It generally triggers a longer minimum jail exposure on a first offense, a mandatory chemical-dependency evaluation, and mandatory enrollment in the state's 24/7 Sobriety Program (twice-daily breath testing, continuous alcohol monitoring, or an ignition interlock device) as a condition of any restricted driving privilege.

Implied Consent and Refusing the Test

By driving on South Dakota roads, you're deemed to have already consented to a chemical test of your blood, breath, urine, or other bodily substance if an officer has probable cause to believe you're driving under the influence (SDCL 32-23-10). You can still refuse in the moment, but refusal is not a free pass:

• A first refusal triggers an automatic one-year revocation of your license by the DPS, handled as a civil/administrative matter separate from any criminal DUI case.
• A second or later refusal generally carries a longer revocation than the first — South Dakota enhances repeat refusals, so confirm the exact current length with the DPS if this isn't your first refusal.
• Your refusal can be used against you. Under SDCL 32-23-10.1, the fact that you refused testing is admissible as evidence in the criminal DUI prosecution itself — refusing does not keep it out of court.

The Administrative Revocation and the 120-Day Hearing Deadline

In South Dakota, this pre-conviction, agency-level license action is tied to a refusal to test (rather than a separate suspension simply for failing the test). Here's how it works and why the timeline matters:

• The South Dakota Department of Public Safety — specifically its driver licensing division — is the agency that carries out the revocation and hears any challenge to it.
• Under SDCL 32-23-11, if you want to contest the revocation, you must request a hearing within 120 days of the arrest. If the DPS finds the officer complied with the legal requirements for advising you of the consequences of refusal, and that you did in fact refuse, it will revoke your license for one year regardless of what happens later in the criminal case.
• Do not sit on this. Even though 120 days is more breathing room than the short windows (sometimes as little as 7-10 days) that some other states use, it is still an affirmative deadline you have to meet with a written request — it is not something your defense attorney or the court does for you automatically, and it is easy to let slip while you're focused on the criminal charge.
• This administrative hearing is separate from your criminal court case. Losing the administrative hearing doesn't mean you'll be convicted of DUI, and winning it doesn't make the criminal charge go away.

First-Offense Penalties: License, Jail, Fines, and the Interlock Question

A first DUI conviction in South Dakota is a Class 1 misdemeanor (SDCL 32-23-2), which generally carries exposure up to the standard Class 1 misdemeanor maximum used across South Dakota's criminal code — confirm the current maximum jail and fine figures with the court or a defense attorney, since these general misdemeanor caps are set separately from the DUI statute itself and can be adjusted by the legislature.

• License revocation: a minimum of 30 days, and the court can extend the restriction (or revoke further) for up to an additional year depending on the facts.
• Limited/restricted driving privileges: after showing proof of financial responsibility, a first-offense defendant may be allowed to drive for things like work, school, medical appointments, and 24/7 Sobriety Program testing during part of the revocation.
• Ignition interlock device (IID): South Dakota is one of the few states that does not mandate an interlock for every first-offense conviction. Whether one is required depends on the facts — a high BAC (0.17%+), a prior record, or a judge's discretion can all lead to an interlock or 24/7 Sobriety Program condition being imposed anyway.

Because exact dollar fine amounts and day-for-day jail ranges depend on the misdemeanor classification schedule and can change, don't rely on a number you saw in a forum or an out-of-state website — ask the clerk of court in the county where you're charged, or a local defense attorney, what currently applies.

The Lookback (Washout) Period: 10 Years

South Dakota uses a 10-year lookback period for counting prior DUI convictions toward enhancement (SDCL 32-23-4.1). A prior DUI conviction, vehicular battery, or vehicular homicide conviction that's more than 10 years old cannot be used to charge your new case as a second, third, or subsequent offense. One important wrinkle: any time you spent incarcerated for the earlier offense doesn't count toward that 10-year clock — it effectively pauses the lookback period.

When a DUI Becomes a Felony in South Dakota

Unlike some states that require a very high prior count, South Dakota elevates DUI to a felony relatively quickly:

• Third offense within the 10-year lookback: Class 6 felony, with a mandatory minimum one-year license revocation running from sentencing (or from release from any incarceration, whichever is later).
• Fourth offense: Class 5 felony, with a mandatory minimum two years in a state correctional facility and at least a two-year license revocation.
• Fifth and sixth-or-subsequent offenses escalate further under separate statutes, and a habitual pattern of offenses (multiple priors within a 25-year window, with at least two inside the most recent 10 years) can be charged as an even higher-level felony.
• Beyond the repeat-offense track, causing serious injury or death while driving under the influence is prosecuted separately as vehicular battery or vehicular homicide, which carry their own, more severe felony penalties.

What to Do After a DUI Arrest in South Dakota

1. Note the exact date of arrest. The 120-day clock to request an administrative hearing on any refusal-based revocation starts running from that date — write it down and don't rely on memory.
2. If you refused the test, contact the South Dakota Department of Public Safety promptly to find out how and where to file a written request for a hearing, and do it well before the 120-day deadline — don't wait until the last week.
3. Read every piece of paper the officer gave you at the time of arrest, including any temporary permit and the implied-consent advisory. These documents typically state the deadlines and your rights.
4. Talk to a South Dakota criminal defense attorney as soon as possible. The criminal case (which can affect jail time, fines, and a permanent record) and the administrative license matter run on separate tracks, and a lawyer can help you manage both at once.
5. Ask about the 24/7 Sobriety Program and restricted-license options if you need to drive for work, school, or medical care during a revocation — courts and DPS can sometimes authorize limited driving with conditions.
6. Don't assume a first-offense DUI is "no big deal." A conviction affects your driving record for the full 10-year lookback and can turn a later stop into a felony charge.
7. Verify every number before you act on it. BAC limits, refusal penalties, and felony thresholds described here are based on the South Dakota Codified Laws as currently published, but statutes are amended — confirm current figures with the DPS, the court, or a local defense attorney.

This article is general legal information about South Dakota law, not legal advice for your specific situation — consult a licensed South Dakota attorney about your case.