Maryland's Implied Consent Law
Under Transportation Article §16-205.1, any person driving on a Maryland road is deemed to have consented to a chemical test of their blood or breath if lawfully arrested for DUI or DWI. This implied consent does not mean you are legally compelled to take the test — but refusal carries its own set of administrative and potentially criminal consequences.
There are two distinct testing situations in a Maryland DUI stop, and refusal has different legal consequences in each.
The Preliminary Breath Test (PBT) vs. The Evidentiary Test
| Test Type | When Administered | Consequence of Refusal | Admissibility |
|---|---|---|---|
| Preliminary Breath Test (PBT) | At the roadside, before arrest, as part of field investigation | No legal penalty for refusal. Refusal cannot be used as evidence against you. | Result is generally not admissible in court |
| Evidentiary Breath Test | At the police station after arrest, on a certified instrument (e.g., Intoximeter) | Triggers administrative license suspension under §16-205.1. May be considered by the trier of fact under MPJI-Cr 4:10.5. Additional criminal penalty possible under §21-902(g) with advance notice. | Result is admissible if properly administered |
Consequences of Refusing the Evidentiary Test
Refusing the evidentiary breath test at the station after arrest triggers the following consequences under Maryland law:
- Administrative license suspension — 270 days for a first refusal; 2 years (or revocation) for a second or subsequent refusal under §16-205.1
- Trier of fact consideration — The jury or judge may consider the refusal as evidence of consciousness of guilt, though they are instructed under MPJI-Cr 4:10.5 that refusal may be based on reasons consistent with innocence
- Additional criminal penalty — Under TR §21-902(g), if convicted of any §21-902 violation and the trier of fact finds beyond a reasonable doubt that you knowingly refused testing arising from the same stop, an additional sentence of up to 2 months imprisonment and/or a $500 fine applies — but only if the State's Attorney provided advance written notice
- Mandatory Ignition Interlock — Under §21-902.3, if convicted of DWI or drug impairment and the court finds test refusal, mandatory IID participation for one year is required
This is a fact-specific analysis with no universal answer. Without a BAC reading, the State's criminal case relies entirely on officer observations and field sobriety test performance — which can sometimes be easier to challenge than a documented BAC level. However, the administrative suspension for refusal is longer than for a test result of 0.08%–0.14%, and the refusal can be used as an adverse inference at trial. An experienced Maryland DUI attorney can evaluate your specific facts and advise accordingly.
Defending a DUI Without a BAC Reading
When a defendant refused chemical testing, the State must prove impairment through other means. This creates a case built entirely on the officer's subjective observations and field sobriety test performance — both of which are subject to vigorous challenge:
- Lawfulness of the traffic stop — Without a BAC reading, the stop itself becomes the critical chokepoint. An unlawful stop suppresses all subsequent evidence.
- Field sobriety test challenges — The officer's administration of the HGN, Walk-and-Turn, and One-Leg Stand tests must comply with NHTSA protocols. Deviations are documented through cross-examination and body camera review.
- Body camera footage — BWC recordings often show the defendant's actual behavior, which frequently differs from what the charging documents describe.
- Medical and environmental factors — Fatigue, medical conditions, road conditions, and weather can explain the observations the officer attributed to alcohol impairment.