Legal BAC Limits in Maryland and St. Mary’s County

In St. Mary’s County, Maryland, the legal Blood Alcohol Concentration (BAC) limit for most drivers is 0.08%. If your BAC meets or exceeds this threshold, you can be charged with Driving Under the Influence (DUI) under Maryland law.

Special categories of drivers face stricter limits:

• Commercial drivers: 0.04% BAC

• Drivers under age 21: 0.02% BAC

Understanding these legal thresholds is crucial because a DUI arrest can occur even if you feel only mildly impaired. Maryland law does not require proof of actual impairment once the legal BAC limit is exceeded.

Learn more about Maryland’s DUI statute § 21–902.

DUI Penalties in St. Mary’s County: What to Expect

The penalties for DUI in Maryland are serious and escalate with each subsequent offense. Even a first-time offender in St. Mary’s County may face:

• Up to 1 year in jail

• Fines up to $1,000

• up to 270 day license suspension

• Mandatory Ignition Interlock Device installation at your own expense

Repeat DUI offenses may result in:

• Increased jail time (up to 10 years)

• Heavier fines (up to $10,000)

• Longer license suspensions

The Maryland Motor Vehicle Administration (MVA) may impose additional administrative penalties, including points on your license and insurance consequences. For more on administrative consequences, visit the MVA Ignition Interlock Program.

Approved Ignition Interlock Providers in Maryland

If your DUI case results in a court order or MVA requirement to install an ignition interlock device (IID), you must use a certified provider to remain in compliance. These devices are typically installed in your vehicle to prevent operation if alcohol is detected on your breath. Below is a list of approved ignition interlock providers serving St. Mary’s County and throughout Maryland:

• Smart Start Interlock – 1-800-880-3394

• Intoxalock – 1-833-259-3046

• Alcohol Detection Systems – 1-888-786-7384

• RoadGuard Interlock – 1-800-332-6858

• Guardian Interlock – 1-800-499-0994

• LifeSafer – 1-800-374-5760

• Low Cost Interlock – 1-844-276-0549

• Sens-O-Lock – 410-995-9080

It’s important to coordinate with your attorney and confirm MVA requirements before scheduling installation. Failure to comply with the interlock program terms can result in additional penalties, including extended license suspension or revocation.

For more information on Maryland’s ignition interlock program, visit the MVA Ignition Interlock Program page.

Common DUI Defenses in Maryland Courts

If you’ve been charged with DUI, you’re not without options. An experienced DUI defense attorney in St. Mary’s County can help you explore legal strategies tailored to your case. Potential defenses include:

• Challenging BAC results due to improperly calibrated or faulty testing equipment

• Questioning the legality of the traffic stop(e.g., lack of probable cause/Reasonable Articulable Suspicion)

• Highlighting procedural errors in your arrest, booking, or field sobriety tests

• Asserting a medical condition or other external factor that influenced BAC levels

DUI cases are highly fact-specific, and success often depends on detailed legal analysis and proactive representation. That’s why it’s critical to work with a lawyer familiar with St. Mary’s County courts and prosecutors.

Why You Need a DUI Defense Lawyer in St. Mary’s County

Navigating a DUI charge without legal counsel can be risky. At Piereck Law, LLC, we focus on criminal defense and DUI representation in Southern Maryland, including St. Mary’s County. Our firm provides:

• Strategic case evaluation based on years of local experience

• Skilled negotiations to reduce or dismiss charges

• Trial preparation, when needed, to fight for your rights in court

• Guidance through MVA license hearings and interlock compliance

Every DUI case is different. Whether you're facing your first arrest or have prior convictions, our team can help you protect your license, your freedom, and your future.

If you're looking for a DUI attorney in St. Mary’s County, contact Piereck Law, LLC today for a consultation.

Next Steps If You’ve Been Arrested for DUI in Southern Maryland

If you've recently been charged with driving under the influence in Maryland, act quickly:

1. Do not admit guilt or discuss your case with anyone but your attorney.

2. If you blew over 0.08 or refused the test, you have 30 days to either request a hearing or get an interlock installed, or your license will be suspended. Talk to your lawyer to figure out which option is best for you.

3. Contact a DUI lawyer who understands the legal landscape in St. Mary’s County.

A conviction can carry lasting consequences—including jail time, job loss, and increased insurance premiums. Let us help you build a strong defense and chart a path forward.